All questions of Number System & Representation for Electronics and Communication Engineering (ECE) Exam

Binary subtraction of 100101 – 011110 is?
  • a)
    000111
  • b)
    111000
  • c)
    010101
  • d)
    101010
Correct answer is option 'A'. Can you explain this answer?

Sudhir Patel answered
The rules for Binary Subtraction are :
0 – 0 = 0
0 – 1 = 1 ( Borrow 1)
1 – 0 = 1
1 – 1 = 0

Therefore, The subtraction of 100101 – 011110 = 000111.

No of bits required to represent -6410 in 2’s complement form:
    Correct answer is '7.00'. Can you explain this answer?

    Sudhir Patel answered
    64 in binary form is represented as:
    6410 = (1000000)2
    Taking the 1's complement of the above, we get 0111111
    Adding 1 to the 1's complement, we get the 2's complement representation of the number, i.e. 1000000.
    Since there is a 1 in the LSB, the number is a negative number with value 64.
    ∴ The 2's complement of -6410 contains 7 bits.

    Which of the following is equal to x3?
    • a)
      x6x3
    • b)
      x6 + x3
    • c)
      x6 / x3
    • d)
      (x6)3
    Correct answer is option 'C'. Can you explain this answer?

    Explanation:

    To solve the equation x3, we need to understand what the exponent 3 represents. In mathematics, an exponent signifies that the base number is multiplied by itself a certain number of times.

    So, x3 can be written as x * x * x. This means that x is multiplied by itself three times.

    Now, let's evaluate the given options to find the one that equals x3.

    a) x6x3:
    Here, x6 represents x multiplied by itself six times. Multiplying it by x3 would result in x9, not x3. So, this option is incorrect.

    b) x6 x3:
    This option is a bit unclear due to the formatting. It could be interpreted as x6 multiplied by x3, which would result in x9. However, if we assume that there is a missing operator between x6 and x3, then it would be x6 * x * x * x, which is equal to x9. Therefore, this option is also incorrect.

    c) x6/ x3:
    This option represents x6 divided by x3. When dividing two expressions with the same base (x in this case), we subtract the exponents. So, x6 divided by x3 is equal to x(6-3) = x3. Therefore, this option is correct.

    d) (x6)3:
    This option represents x6 raised to the power of 3. When raising an expression with an exponent to another exponent, we multiply the exponents. So, (x6)3 is equal to x(6*3) = x18, not x3. Therefore, this option is incorrect.

    Conclusion:
    Among the given options, option 'C' (x6/ x3) is the only one that equals x3. The other options either result in x9 or x18.

    Perform the subtraction and represent your answer in 2’s complement form (10010)2 - (10111)2
    • a)
      –(11011)2
    • b)
      (11011)
    • c)
      (00101)2
    • d)
      –(00101)2
    Correct answer is option 'B'. Can you explain this answer?

    Sorry, but I need more information about the subtraction problem in order to provide a specific answer. Could you please provide the numbers you want to subtract?

    The decimal number (57.375)10 when converted to binary number takes the form:
    • a)
      (111001.011)2
    • b)
      (100111.110)2
    • c)
      (110011.101)2
    • d)
      (111011.011)2
    Correct answer is option 'A'. Can you explain this answer?

    Bhavya Patel answered
    Conversion of Decimal to Binary
    To convert a decimal number to binary, we use the following steps:
    1. Divide the decimal number by 2.
    2. Write down the remainder (0 or 1).
    3. Divide the quotient again by 2 and write down the remainder.
    4. Repeat step 3 until the quotient becomes 0.

    Conversion of Fractional Part
    To convert the fractional part of a decimal number to binary, we use the following steps:
    1. Multiply the fractional part by 2.
    2. Write down the integer part.
    3. Repeat step 1 with the fractional part until the fractional part becomes 0 or the desired number of bits is obtained.

    Conversion of (57.375)10 to Binary
    1. We divide 57 by 2 to obtain a quotient of 28 and a remainder of 1.
    2. We divide 28 by 2 to obtain a quotient of 14 and a remainder of 0.
    3. We divide 14 by 2 to obtain a quotient of 7 and a remainder of 0.
    4. We divide 7 by 2 to obtain a quotient of 3 and a remainder of 1.
    5. We divide 3 by 2 to obtain a quotient of 1 and a remainder of 1.
    6. We divide 1 by 2 to obtain a quotient of 0 and a remainder of 1.
    7. The integer part of the binary number is obtained by writing the remainders in reverse order: (111001)2.

    To obtain the fractional part, we multiply 0.375 by 2 to obtain 0.75. The integer part is 0, so we write down 0. We then multiply 0.75 by 2 to obtain 1.5. The integer part is 1, so we write down 1. We then multiply 0.5 by 2 to obtain 1. The integer part is 1, so we write down 1. The fractional part is 0.011.

    Therefore, the binary representation of (57.375)10 is (111001.011)2. The correct answer is option A.

    Which of the following is largest among others?
    • a)
      √0.0004
    • b)
      √0.0121
    • c)
      (0.1)2
    • d)
      0.12
    Correct answer is option 'D'. Can you explain this answer?

    Qamar Rao answered
    There are no options provided, so it is not possible to determine which of the following is largest among others.

    Perform binary subtraction: 101111 – 010101 = ?
    • a)
      100100
    • b)
      010101
    • c)
      011010
    • d)
      011001
    Correct answer is option 'C'. Can you explain this answer?

    Tanishq Joshi answered
    To perform binary subtraction, you need to borrow from the next higher bit if necessary. Here is the step-by-step process for subtracting 101111:

    101111
    - 1
    ------
    101110

    So, subtracting 1 from 101111 gives us the result 101110.

    Divide the binary numbers: 111101 ÷ 1001 and find the remainder.
    • a)
      0010
    • b)
      1010
    • c)
      1100
    • d)
      0111
    Correct answer is option 'D'. Can you explain this answer?

    The binary number 111101 is equivalent to the decimal number 61.

    Since it is not specified how the division should be done, I will assume that you want to divide it by 2.

    When you divide 61 by 2, the quotient is 30 and the remainder is 1.

    Therefore, 111101 divided by 2 is equal to 11110 with a remainder of 1.

    If the three-fifth of a number is equal to 70% of another number, what is the ratio between the first number and second number?
    • a)
      6 : 7
    • b)
      7 : 6
    • c)
      3 : 4
    • d)
      4 : 3
    Correct answer is option 'B'. Can you explain this answer?

    Ravi Singh answered
     Let the numbers be a and b.
    So, according to the question,
    a * 3/5 = 70% of b
    3a/5 = 70b/100
    a/b = (70 * 5)/(100 * 3) = 7/6
    So, the ration between a and b is 7 : 6.

    Given the following binary number in 32-bit (single precision) IEEE-754 format:
    00111110011011010000000000000000
    The decimal value closest to this floating-point number is
    • a)
      1.45 × 101
    • b)
      1.45 × 10-1
    • c)
      2.27 × 10-1
    • d)
      2.27 × 101
    Correct answer is option 'C'. Can you explain this answer?

    Imtiaz Ahmad answered
    32-bit floating-point representation of a binary number in IEEE- 754 is,

    Given binary number is
    00111110011011010000000000000000
    Here, sign bit is 0. So, number is positive.

    Exponent bits = E = 01111100 = 124 (in decimal)
    Mantissa bits M = 11011010000000000000000
    In IEEE-754 format, 32-bit (single precision)
    (-1)s × 1.M × 2E – 127
    = (-1)0 × 1.1101101 × 2124 – 127
    = 1.1101101 × 2-3
    = (1 + 2-1 + 2-2 + 2-4 + 2-5 + 2-7) × 2-3
    = 0.231 = 2.31 × 10-1 ≈ 2.27 × 10-1

    What is the addition of the binary numbers 11011011010 and 010100101?
    • a)
      0111001000
    • b)
      1100110110
    • c)
      11101111111
    • d)
      10011010011
    Correct answer is option 'C'. Can you explain this answer?

    Ayush Banerjee answered
    Problem:
    Find the addition of the binary numbers 11011011010 and 010100101.

    Solution:
    To add binary numbers, we follow the same rules as adding decimal numbers. We start from the rightmost bit and move towards the left, carrying over any carry values.

    Step 1: Write the numbers vertically with the bits aligned.

    11011011010
    + 010100101
    ________________

    Step 2: Start adding the bits from right to left.

    11011011010
    + 010100101
    ________________
    111011011

    Step 3: Carry over any carry values.

    11011011010
    + 010100101
    ________________
    111011011

    Step 4: Continue adding the remaining bits.

    11011011010
    + 010100101
    ________________
    11101111111

    Step 5: The addition is complete.

    Therefore, the addition of the binary numbers 11011011010 and 010100101 is 11101111111, which corresponds to option 'C'.

    What will be the value of x, if 5(x + 3) = 25(3x - 4)?
    • a)
      11/5
    • b)
      11/6
    • c)
      5/11
    • d)
      6/11
    Correct answer is option 'A'. Can you explain this answer?

    Sarita Yadav answered
    Given, 5(x + 3) = 25(3x - 4)
    We can write it as -
    5(x + 3) = 52 x (3x - 4)
    Or,
    x + 3 = 2(3x - 4)
    x + 3 = 6x - 8
    or, 5x = 11
    So, x = 11/5

    What will be the result of 1397 x 1397?
    • a)
      1951609
    • b)
      1951608
    • c)
      1951699
    • d)
      None of the above
    Correct answer is option 'A'. Can you explain this answer?

    Mohit Agarwal answered
    Solution:

    To find the result of 1397 x 1397, we will multiply these two numbers together.

    Step 1: Multiply the ones place digits
    - 7 x 7 = 49

    Step 2: Multiply the tens place digits
    - 9 x 9 = 81

    Step 3: Multiply the hundreds place digits
    - 3 x 3 = 9

    Step 4: Multiply the thousands place digits
    - 1 x 1 = 1

    Step 5: Write the individual results
    - Result of step 1: 49
    - Result of step 2: 81 (write this on the tens place)
    - Result of step 3: 9 (write this on the hundreds place)
    - Result of step 4: 1 (write this on the thousands place)

    Step 6: Add the individual results
    - 49 + 81 + 9 + 1 = 140

    Therefore, the result of 1397 x 1397 is 140.

    However, none of the given options match the correct result. The correct answer should be 140, not any of the options provided.

    If x, y, and z are said to be the real numbers, then what is the value of (x - y)3 + (y - z)3 + (z - x)3 ?
    • a)
      0
    • b)
      (x - y)
    • c)
      3(x - y) (y - z) (z - x)
    • d)
      (x - y) (y - z) (z - x)
    Correct answer is option 'C'. Can you explain this answer?

    Ravi Singh answered
    Suppose a = (x - y), b = (y - z), and c = (z - x)
    On adding a, b, and c we will get
    a + b + c = x -y + y - z + z - x
    => a + b + c =0
    So, a3 + b3 + c3 = 3abc [because if a + b + c = 0, then a3 + b3 + c3 = 3abc]
    We can say that (x - y)3 + (y - z)3 + (z - x)3 = 3 (x - y) (y - z) (z - x)

    The denominator of a fraction is 3 more than its numerator. If the denominator is decreased by 2, and the numerator is increased by 7, we will get 2. What will be the sum of the numerator and denominator of that fraction?
    • a)
      6
    • b)
      13
    • c)
      31
    • d)
      14
    Correct answer is option 'B'. Can you explain this answer?

    Pranav Bhatia answered
    Let's assume the numerator of the fraction is x. According to the question, the denominator is 3 more than the numerator, so it will be x + 3.

    According to the second part of the question, when the denominator is decreased by 2 and the numerator is increased by 7, we get a new fraction equal to 2.

    The new numerator will be x + 7, and the new denominator will be (x + 3) - 2 = x + 1.

    So, we have the equation (x + 7) / (x + 1) = 2.

    To solve this equation, we can cross-multiply:

    2(x + 1) = x + 7

    2x + 2 = x + 7

    2x - x = 7 - 2

    x = 5

    Now that we have found the value of x, we can substitute it back into the equation to find the denominator:

    Denominator = x + 3 = 5 + 3 = 8

    The numerator is 5 and the denominator is 8. The sum of the numerator and denominator is 5 + 8 = 13.

    Therefore, the correct answer is option B, 13.

    On multiplication of (10.10) and (01.01), we get ____________
    • a)
      101.0010
    • b)
      0010.101
    • c)
      011.0010
    • d)
      110.0011
    Correct answer is option 'C'. Can you explain this answer?

    Aashna Pillai answered
    Explanation:

    To multiply the binary numbers (10.10) and (01.01), we can use the method of binary multiplication similar to decimal multiplication.

    Step 1: Write the numbers vertically and align the decimal points.
    ```
    10.10
    x 01.01
    ```

    Step 2: Multiply the rightmost digits of the second number by the first number.
    ```
    10.10
    x 01.01
    ------------
    10.10 (Multiply 1st digit of 2nd number by 10.10)
    ```

    Step 3: Multiply the second rightmost digits of the second number by the first number, but shifted one place to the left.
    ```
    10.10
    x 01.01
    ------------
    10.10 (Multiply 1st digit of 2nd number by 10.10)
    + 10.10 (Multiply 2nd digit of 2nd number by 10.10, shifted 1 place left)
    ------------
    110.10
    ```

    Step 4: Add the partial products.
    ```
    10.10
    x 01.01
    ------------
    10.10 (Multiply 1st digit of 2nd number by 10.10)
    + 10.10 (Multiply 2nd digit of 2nd number by 10.10, shifted 1 place left)
    ------------
    110.10 (Add the partial products)
    ```

    Step 5: Adjust the decimal point of the result by counting the total number of digits after the decimal point in both numbers.
    In this case, there are 2 digits after the decimal point in each number, so we need to shift the decimal point 4 places to the left in the result.
    ```
    10.10
    x 01.01
    ------------
    110.10 (Add the partial products)
    ```
    After shifting the decimal point 4 places to the left, we get the final result as 0.11010.

    Conversion to Decimal:
    To convert the binary result to decimal, we multiply each digit by the corresponding power of 2 and sum them up.
    ```
    0.11010 = (0 * 2^-1) + (1 * 2^-2) + (1 * 2^-3) + (0 * 2^-4) + (1 * 2^-5)
    = 0 + 0.25 + 0.125 + 0 + 0.03125
    = 0.40625
    ```

    Therefore, the correct answer is option C) 0.0110010 in binary or 0.40625 in decimal.

    A floating-point (FP) number is said to be normalized, if the most significant bit of the mantissa is
    • a)
      1
    • b)
      0
    • c)
      -1
    • d)
      2
    Correct answer is option 'A'. Can you explain this answer?

    Imtiaz Ahmad answered
    A floating-point (FP) number is said to be normalized, if the most significant bit of the mantissa is 1.
    • If the exponent is all zeros, the floating point number is denormalized and the most significant bit of the mantissa is known to be zero.
    • The floating number representation has four parts:1. The first part represents a single fixed point number is called the mantissa.
    • The second part designates the position of the decimal point and is called the exponent.
    • The mantissa always a positive number holds the significant digits of the floating point number.
    • The exponent indicates the positive or negative power of the radix that the mantissa and sign should be multiplied by.

    The 2’s complement of the binary number 1101101 is
    • a)
      0101110
    • b)
      0111110
    • c)
      0110010
    • d)
      0010011
    Correct answer is option 'D'. Can you explain this answer?

    Sudhir Patel answered
    Concept:
    1’s complement representation of a binary number is obtained by toggling all the bits, i.e. replacing 1 with 0, and 0 with 1.
    2’s complement representation of a binary number is obtained by adding 1 to the 1’s complement representation.
    Application:
    Given the binary number is 1101101
    Taking the 1's complement of the above, we replace all the 1's with 0's and all the 0's with 1's to get:
    1's complement of 1101101 = 0010010
    Adding 1 to the 1's complement, we get the 2's complement as:
    0010010 + 1 = 0010011

    What is the largest positive value that can be represented by an 8 bit 2’s complement number
    • a)
      127
    • b)
      128
    • c)
      255
    • d)
      256
    Correct answer is option 'A'. Can you explain this answer?

    In 8-bit, the range of values that can be represented is from 0 to 255. Therefore, the largest positive value that can be represented by an 8-bit number is 255.

    The 2’s complement of 101101 is
    • a)
      100011
    • b)
      101100
    • c)
      010011
    • d)
      110011
    Correct answer is option 'C'. Can you explain this answer?

    Amrutha Chawla answered
    The number "2" is a whole number that comes after 1 and before 3. It is an even number and is the smallest prime number. It is also the only even prime number. In mathematics, 2 is the base of the binary number system, which is widely used in computer science and digital electronics. Additionally, 2 is often used to represent a couple or a pair of items, such as in the phrase "two of a kind."

    Suppose x = a(b - c), y = b(c - a), z = c(a - b), then what is the value of (x/a)3 + (y/b)3 + (z/c)3?
    • a)
      3xyz/abc
    • b)
      2xyz/abc
    • c)
      xyz/abc
    • d)
      None of the above
    Correct answer is option 'A'. Can you explain this answer?

    Wahida Thakkar answered
    Understanding the Variables
    Given the expressions:
    - x = a(b - c)
    - y = b(c - a)
    - z = c(a - b)
    These define how x, y, and z relate to the variables a, b, and c.
    Objective
    We aim to find the value of (x/a)³ + (y/b)³ + (z/c)³.
    Substituting Values
    Start by substituting x, y, and z into the expression:
    - (x/a) = (b - c)
    - (y/b) = (c - a)
    - (z/c) = (a - b)
    Thus, we need to evaluate:
    (b - c)³ + (c - a)³ + (a - b)³.
    Using the Identity
    Utilize the algebraic identity for the sum of cubes:
    - a³ + b³ + c³ - 3abc = (a + b + c)(a² + b² + c² - ab - ac - bc).
    In our case:
    - Let a = b - c
    - Let b = c - a
    - Let c = a - b
    This leads to:
    (b - c)³ + (c - a)³ + (a - b)³ = 3(b - c)(c - a)(a - b).
    Final Calculation
    Now, we can express (b - c)(c - a)(a - b):
    xyz = a(b - c) * b(c - a) * c(a - b).
    Thus, the expression simplifies to:
    (b - c)³ + (c - a)³ + (a - b)³ = 3xyz/abc.
    Conclusively, we find:
    Answer
    The value of (x/a)³ + (y/b)³ + (z/c)³ = 3xyz/abc, which confirms that the correct answer is option 'A'.

    What is the range of the exponent E in IEEE 754 Double Precision (Binary64) format?
    • a)
      -1022 ≤  E ≤ 1022
    • b)
      -1023 ≤  E ≤ 1023
    • c)
      -1023 ≤ E ≤ 1022
    • d)
      -1022 ≤  E ≤ 1023
    Correct answer is option 'D'. Can you explain this answer?

    Tanvi Ahuja answered
    To find the range of the exponent E in IEEE 754 Double Precision (Binary64) format, we need to consider the bias and the number of bits used to represent the exponent.

    In IEEE 754 Double Precision format, the exponent E is represented using 11 bits. The bias for the exponent is 1023.

    The range of the exponent E can be calculated as follows:

    Minimum exponent = 1 - bias = 1 - 1023 = -1022
    Maximum exponent = (2^11) - 1 - bias = 2047 - 1023 = 1024

    Therefore, the range of the exponent E in IEEE 754 Double Precision format is -1022 to 1024.

    The sum of the numerator and denominator of a fraction is 11. If we add 2 to both numerator and denominator, the fraction will be increased by 1/24. What is the difference between the numerator and denominator of that fraction?
    • a)
      1
    • b)
      2
    • c)
      6
    • d)
      8
    Correct answer is option 'A'. Can you explain this answer?

    Ravi Singh answered
    Let the numerator of the fraction be x, so the denominator will be 11 - x
    So, the fraction = x/11 - x
    On adding 2 in both numerator and denominator, according to the question, the fraction will be -
    (x + 2)/(11 - x + 2) = (x)/(11 - x) + 1/24
    (x + 2)/(13 - x) - (x)/(11 - x) = 1/24
    [11x + 22 - x2 -2x - 13x + x2]/(13 - x) (11 - x) = 1/24
    After solving the above equation, we will get
    => 528 - 96x = 143 - 24x + x2
    x2 + 72x - 385 = 0
    (x + 77) (x - 5) = 0
    So, x =5
    So, numerator = 5
    and, denominator = 11 - 5 = 6
    Difference between both is = 6 - 5 = 1

    If we decide to stay away from IEEE 754 format by making our Exponent field 10 bits wide and our Mantissa field 21 bits wide, then which of the following statement is TRUE?
    • a)
      None of the above
    • b)
      It will provide less precision as there will be fewer Mantissa bits
    • c)
      It will provide more precision as there will be fewer Mantissa bits
    • d)
      It will not change the precision
    Correct answer is option 'B'. Can you explain this answer?

    Starcoders answered
    The Institute of Electrical and Electronics Engineers created the IEEE Standard for Floating-Point Arithmetic (IEEE 754) in 1985 as a technical standard for floating-point calculation (IEEE). The standard addressed several issues encountered in various floating-point implementations.
    IEEE 754 has 3 basic components are Sign, exponent, and  Mantissa.
    Given that,
    Exponent field =10 bits
    Mantissa field = 21 bits 
    Sign= 1 bit (represents the positive number or negative number)
    Bias=Excess=2n-1 where n is the number of bits in the Exponent.
    To get Number = (-1)S x (1.M) x BE-Bias
    Fewer mantissa bits mean less precision. The smallest change that can be represented in floating-point representation is called precision. In single precision, the mantissa is having 23 bits, and double-precision the mantissa is having 52 bits are required. Hence the less precision as there will be fewer Mantissa bits.
    Hence the correct answer is It will provide less precision as there will be fewer Mantissa bits.

    The decimal floating-point number -40.1 represented using IEEE-754 32-bit representation and written in hexadecimal form is _____
    • a)
      0xC2206000
    • b)
      0xC2006666
    • c)
      0xC2006000
    • d)
      0xC2206666
    Correct answer is option 'D'. Can you explain this answer?

    Starcoders answered
    32-bit floating-point representation of a binary number in IEEE- 754 is

    In IEEE-754 format, 32-bit (single precision)
    (-1)s × 1.M × 2E – 127
    Calculation:
    Convert: 40.1 to binary
    Step 1: convert 40

    (40)10 = (101000)2
    Step 2: convert .1 to binary
    0.1 × 2 = 0.2           (0)
    0.2 × 2 = 0.4           (0)
    0.4 × 0.2 = 0.8        (0)
    0.8 × 0.2 = 1.6        (1)
    0.6 × 0.2 = 1.2        (1)
    0.2 × 0.2 = 0.4        (0)  and so on
    Given binary number is
    (40.1)10 = (101000.000110011001100…)2
    (40.1)10 = 1.0100 0000 1100 1100 … × 25
    Signed (1 bit) = 1 (given number is negative)
    Exponent (8 bit) = 5 + 127 = 132
    ∴ Exponent = (132)10 = (1000 0100)2
    Mantissa (23 bits ) = 0100 0000 1100 1100 1100 110

    (1100 0010 0010 0000 0110 0110 0110 0110)2 = (C2206666)16
    (C2206666)16 = 0xC2206666

    X = 00110 and Y = 10011 are two binary numbers represented in 2's complement format. The sum of X and Y represented in 2's complement format using 5 bits is _____
    • a)
      11001
    • b)
      01001
    • c)
      10100
    • d)
      10010
    Correct answer is option 'A'. Can you explain this answer?

    Sudhir Patel answered
    X = 00110
    since, the MSB = 0
    ∴ it is a positive number.
    Decimal equivalent: 0 + 1 × 22 + 1 × 21 + 0 × 20 = + 6
    Y = 10011
    since, the MSB = 1 
    ∴ it is a negative number,
    We need to take the 2's complement of Y, that is.
    1's complement (Y) + 1
    01100 + 1
    ⇒ 01101
    Decimal equivalent → 0 + 1 × 23 + 1 × 22 + 0 + 1 × 20 → -13
    The sum of X and Y is
    +6 - 13 = - 7
    The 2's complement of - 7
    → 1's complement of 7 + 1
    → 1's complement of 00111 + 1
    → 11000 + 1 → 11001

    What will be the remainder when 636 is divided by 215?
    • a)
      3
    • b)
      2
    • c)
      1
    • d)
      None of the above
    Correct answer is option 'C'. Can you explain this answer?

    To find the remainder when 636 is divided by 215, we can use the method of long division.

    Step 1: Divide the first digit of the dividend (6) by the divisor (2). The quotient is 3.
    Step 2: Multiply the divisor (215) by the quotient obtained in Step 1 (3), and subtract the result from the first three digits of the dividend (636). The result is 636 - (3 * 215) = 636 - 645 = -9.
    Step 3: Bring down the next digit of the dividend (3) and append it to the remainder obtained in Step 2 (-9), resulting in -93.
    Step 4: Divide the first two digits of the new dividend (-9) by the divisor (2). The quotient is -4.
    Step 5: Multiply the divisor (215) by the quotient obtained in Step 4 (-4), and subtract the result from the first two digits of the new dividend (-9). The result is -9 - (-4 * 215) = -9 + 860 = 851.
    Step 6: Bring down the next digit of the dividend (6) and append it to the remainder obtained in Step 5 (851), resulting in 8516.
    Step 7: Divide the first three digits of the new dividend (851) by the divisor (2). The quotient is 425.
    Step 8: Multiply the divisor (215) by the quotient obtained in Step 7 (425), and subtract the result from the first three digits of the new dividend (8516). The result is 8516 - (425 * 215) = 8516 - 91375 = -82859.
    Step 9: Bring down the next digit of the dividend (0) and append it to the remainder obtained in Step 8 (-82859), resulting in -828590.
    Step 10: Divide the first four digits of the new dividend (-8285) by the divisor (2). The quotient is -4142.
    Step 11: Multiply the divisor (215) by the quotient obtained in Step 10 (-4142), and subtract the result from the first four digits of the new dividend (-828590). The result is -828590 - (-4142 * 215) = -828590 + 890230 = 61640.
    Step 12: Bring down the next digit of the dividend (9) and append it to the remainder obtained in Step 11 (61640), resulting in 616409.
    Step 13: Divide the first five digits of the new dividend (61640) by the divisor (2). The quotient is 30820.
    Step 14: Multiply the divisor (215) by the quotient obtained in Step 13 (30820), and subtract the result from the first five digits of the new dividend (616409). The result is 616409 - (30820 * 215) = 616409 - 6632300 = -6015891.
    Step 15: Bring down the next digit of the dividend (1) and append it to the remainder obtained in Step 14 (-6015891), resulting in -60158911.

    Since the dividend (-60158911) is less than the divisor (215), we cannot continue the division process. The remainder is the last value obtained in the process, which is -60158911.

    What is the 1’s complement of (10011)2?
    • a)
      (10011)2
    • b)
      (01001)2
    • c)
      (11100)2
    • d)
      (01100)2
    Correct answer is option 'D'. Can you explain this answer?

    Avik Yadav answered
    1's Complement of (10011)2
    To find the 1's complement of a binary number, we simply flip all the bits in the number. In this case, we have the binary number (10011)2.

    Steps to find the 1's complement:
    - Flip all the bits in the given binary number
    - (10011)2 becomes (01100)2
    Therefore, the 1's complement of (10011)2 is (01100)2.
    So, the correct answer is option 'D' - (01100)2.

    Perform binary addition: 101101 + 011011 = ?
    • a)
      011010
    • b)
      1010100
    • c)
      101110
    • d)
      1001000
    Correct answer is option 'D'. Can you explain this answer?

    Performing binary addition:
    To perform binary addition, we follow a set of rules similar to decimal addition. The rules are as follows:

    - 0 + 0 = 0
    - 0 + 1 = 1
    - 1 + 0 = 1
    - 1 + 1 = 10 (carry 1 and write 0)

    Given binary numbers: 101101 and 011011

    Let's perform the addition step by step:

    Step 1: Start from the rightmost bit and add the corresponding bits.
    1
    0 1 1 0 1 0 1 (101101)
    + 0 1 1 0 1 1 (011011)
    ----------------
    1 0 0 1 0 0 0 (1001000)

    Step 2: Carry over any 1s to the next column (if applicable).
    1
    0 1 1 0 1 0 1 (101101)
    + 0 1 1 0 1 1 (011011)
    ----------------
    1 0 0 1 0 0 0 (1001000)

    Since there are no more columns to add, we have our final result:

    101101 + 011011 = 1001000

    Therefore, the correct answer is option 'D' (1001000).

    In binary addition, each bit represents a power of 2, where the rightmost bit is 2^0, the second rightmost bit is 2^1, the third rightmost bit is 2^2, and so on. By adding the corresponding bits, we calculate the sum of each power of 2. If there is a carry (1), it is added to the next column.

    In this case, we have a carry in the fourth column, so we carry over the 1 to the next column. The final result is obtained by combining all the bits together, from left to right.

    Which of the following is the smallest 4-bit negative number stored in its 2's complement representation?
    • a)
      1000
    • b)
      0000
    • c)
      1111
    • d)
      0111
    Correct answer is option 'A'. Can you explain this answer?

    Devansh Chavan answered
    Explanation:


    To find the smallest 4-bit negative number stored in its 2s complement representation, we need to understand how 2s complement works. In 2s complement, the most significant bit (MSB) represents the sign of the number, where 0 is positive and 1 is negative. The rest of the bits represent the magnitude of the number.

    To convert a number to its 2s complement representation, we follow these steps:
    1. Invert all the bits (change 0 to 1 and 1 to 0).
    2. Add 1 to the result of step 1.

    Now, let's find the smallest 4-bit negative number stored in its 2s complement representation.

    Step 1: Invert all the bits of 0000 (smallest 4-bit positive number).
    0000 -> 1111

    Step 2: Add 1 to the result of step 1.
    1111 + 1 = 10000 (5-bit number)

    Since we are limited to 4 bits, we discard the MSB and get the 4-bit 2s complement representation of -8, which is 0000. But this is not the answer since we are looking for the smallest negative number.

    To get the smallest negative number, we need to increment the result of step 1 by 1 before discarding the MSB.

    Step 1: Invert all the bits of 0000 (smallest 4-bit positive number).
    0000 -> 1111

    Step 2: Add 1 to the result of step 1.
    1111 + 1 = 10000 (5-bit number)

    Step 3: Increment the result of step 2 by 1.
    10000 + 1 = 10001 (5-bit number)

    Discard the MSB and we get the smallest 4-bit negative number stored in its 2s complement representation, which is 1000 (equals to -8 in decimal).

    Therefore, the correct answer is option A.

    A register contains a 2’s complement no 10100. Find the value of a register if it is divided by 2
    • a)
      11010
    • b)
      10110
    • c)
      11100
    • d)
      10101
    Correct answer is option 'A'. Can you explain this answer?

    Sahana Kaur answered
    2 is a positive integer and a whole number. It is the smallest prime number and the only even prime number. It is also the base of the binary number system, which is widely used in computer science and digital technology. In mathematics, 2 is an important number in many areas, including algebra, geometry, and number theory. It is also commonly used in measurements and calculations, such as in time (24 hours in a day) and in angles (360 degrees in a circle).

    If the two-third of three - fourth of a number is 34, what will be the 20% of that number?
    • a)
      13.4
    • b)
      13.6
    • c)
      13.7
    • d)
      14
    Correct answer is option 'B'. Can you explain this answer?

    Ravi Singh answered
    Let the number be X.
    According to the question,
    2/3 * 3/4 * X = 34
    6/12 * X = 34
    Or,
    1/2 * X = 34
    So, X = 68
    Now, 20% of 68 is = 68 * 20/100 = 13.6

    Perform multiplication of the binary numbers: 01001 × 01011 = ?
    • a)
      001100011
    • b)
      110011100
    • c)
      010100110
    • d)
      101010111
    Correct answer is option 'A'. Can you explain this answer?

    Ayush Banerjee answered
    The binary number 01001 is equivalent to the decimal number 9.

    If you want to perform multiplication with another binary number, please provide the second binary number.

    Let R1 and R2 be two 4-bit registers that store numbers in 2’s complement form. For the operation R1 + R2, which one of the following values of R1 and R2 gives an arithmetic overflow?
    • a)
      R1 = 1011 and R2 = 1110
    • b)
      R1 = 1100 and R2 = 1010
    • c)
      R1 = 0011 and R2 = 0100
    • d)
      R1 = 1001 and R2 = 1111
    Correct answer is option 'B'. Can you explain this answer?

    Starcoders answered
    Stored numbers in registers R1 and R2 are in 2's complement form. Register size is 4 bits. The range of numbers in 2's complement form is -8 to +7. If R1 + R2, the result is out of the above range, then it is overflow.
    The given data,
    Given two four-bit registers R1 and R2.
    Option 1: R1 = 1011 and R2 = 1110
    False,  
    R1      =  1 0 1 1 = -(0101)= -5
    + R2   =  1 1 1 0 = -(0010)= -2
    -----------------------------------------------
                   1 0 0 1  =           = -7        
    Here No overflow occurred, because sign bit is same for (R1 + R2 ).
    Option 2: R1 = 1100 and R2 = 1010
    True,
    R1      =  1 1 0 0 = -(0100)= -4
    + R2   =  1 0 1 0 = -(0110)= -6
      --------------------------------------------
                  0 1 1 0 =            = -10       
    Here Overflow occurred because the sign bit is different for (R1 + R2 ).
    Option 3: R1 = 0011 and R2 = 0100
    False,
    R1      =   0 0 1 1 = +(0011)= +3
    + R2   =   0 1 0 0 = +(0100)= +4
      --------------------------------------------
                    0 1 1 1                 =   +7       
    Here No overflow occurred, because the sign bit is the same for (R1 + R2 ).
    Option 4: R1 = 1001 and R2 = 1111
    False, 
    R1      =   1 0 0 1 = -(0111)  = -7
    + R2   =   1 1 1 1 = -(0001) = -1
      --------------------------------------------
                    1 0 0 0 =               = -8
    Here No overflow occurred, because the sign bit is the same for (R1 + R2 ).
    Hence the correct answer is R1 = 1100 and R2 = 1010.

    Which is the largest 4-digit number that can be exactly divisible by 66?
    • a)
      9987
    • b)
      9912
    • c)
      9913
    • d)
      9966
    Correct answer is option 'D'. Can you explain this answer?

    Wasima Thakur answered
    Explanation:

    Finding the largest 4-digit number divisible by 66:
    To find the largest 4-digit number that is exactly divisible by 66, we need to start by considering the highest 4-digit number, which is 9999.

    Divisibility rule for 66:
    - A number is divisible by 66 if it is divisible by both 6 and 11.

    Finding the divisibility by 6:
    - The sum of the digits of 9999 is 9+9+9+9 = 36, which is divisible by 6. Therefore, 9999 is divisible by 6.

    Finding the divisibility by 11:
    - Alternating the sum of the digits of 9999, we get (9-9) + (9-9) = 0. Since the result is 0, 9999 is divisible by 11.

    Conclusion:
    - Since 9999 is divisible by both 6 and 11, it is divisible by 66.

    Checking the next highest number:
    - The next highest 4-digit number is 9998, which is not divisible by 66 as it does not meet the divisibility criteria for both 6 and 11.

    Therefore, the largest 4-digit number divisible by 66 is:
    - 9966 (Option D)

    Final Answer:
    - The largest 4-digit number that can be exactly divisible by 66 is 9966.

    Binary subtraction of 101101 – 001011 = ?
    • a)
      100010
    • b)
      010110
    • c)
      110101
    • d)
      101100
    Correct answer is option 'A'. Can you explain this answer?

    To perform binary subtraction, we need to align the numbers vertically and then subtract each corresponding bit.

    101101
    - 101101
    ---------
    0

    Therefore, the binary subtraction of 101101 - 101101 is equal to 0.

    X = 01110 and Y = 11001 are two 5-bit binary numbers represented in two’s complement format. The sum of X and Y represented in two’s complement format using 6 bits is
    • a)
      110111
    • b)
      001000
    • c)
      000111
    • d)
      101001
    Correct answer is option 'C'. Can you explain this answer?

    's complement notation. To subtract Y from X using two's complement notation, we can follow the following steps:

    1. Find the two's complement of Y:
    - Invert all the bits in Y: 11001 becomes 00110.
    - Add 1 to the inverted value: 00110 + 1 = 00111.
    - The two's complement of Y is 00111.

    2. Add X and the two's complement of Y:
    - X = 01110
    - Two's complement of Y = 00111
    - X + two's complement of Y = 01110 + 00111 = 10101

    3. Ignore the carry-out from the leftmost bit (if any), and the result is 0101.

    Therefore, X - Y in two's complement notation is 0101.

    Divide the binary number (011010000) by (0101) and find the quotient.
    • a)
      100011
    • b)
      101001
    • c)
      110010
    • d)
      010001
    Correct answer is option 'B'. Can you explain this answer?

    Abhijeet Joshi answered
    To divide the binary number (011010000) by (0101), we need to perform binary division. Let's go through the steps to find the quotient.

    Step 1: Set up the division
    Write the dividend and divisor in binary format, aligning them properly:

    10010 (dividend)
    /0101 (divisor)

    Step 2: Perform the first division
    Start by dividing the leftmost digits of the dividend (01) by the leftmost digit of the divisor (0). Since we cannot divide 1 by 0, we bring down the next digit (1) from the dividend.

    10010 (dividend)
    /0101 (divisor)
    -

    101 (new dividend)

    Step 3: Perform the second division
    Now, we divide the new dividend (101) by the divisor (0101).

    10010 (dividend)
    /0101 (divisor)
    - 1001
    ----
    101

    Since the divisor is larger than the new dividend, we bring down the next digit (0) from the original dividend.

    Step 4: Perform the third division
    We now divide the new dividend (1010) by the divisor (0101).

    10010 (dividend)
    /0101 (divisor)
    - 1001
    ----
    1010
    - 1010
    ----
    0

    Since the new dividend is now zero, we stop the division process.

    Step 5: Determine the quotient
    The quotient is obtained by combining the remainders from each division step. In our case, the remainders are 1001 and 1010, which gives us the binary quotient: 10011010.

    Step 6: Convert the quotient to decimal
    To convert the binary quotient to decimal, we can use the positional notation. Starting from the rightmost digit, we assign powers of 2 to each digit and sum them up:

    1 * 2^7 + 0 * 2^6 + 0 * 2^5 + 1 * 2^4 + 1 * 2^3 + 0 * 2^2 + 1 * 2^1 + 0 * 2^0 = 128 + 16 + 8 + 2 = 154

    Therefore, the quotient of (011010000) divided by (0101) is 10011010 in binary or 154 in decimal.

    The correct answer is option 'B' (101001).

    A boy has mistakenly multiplied a number by 45 instead of multiplying it with 25. Due to this, the answer was 200 more than the correct answer. What was the number?
    • a)
      15
    • b)
      10
    • c)
      7
    • d)
      None of the above
    Correct answer is option 'B'. Can you explain this answer?

    To solve this problem, let's assume the number that the boy mistakenly multiplied by 45 is 'x'.

    Let's break down the problem into steps:

    Step 1: Calculate the correct answer
    If the boy had multiplied the number 'x' by 25, the correct answer would have been 25x.

    Step 2: Calculate the answer the boy obtained
    The boy multiplied the number 'x' by 45, so the answer he obtained is 45x.

    Step 3: Find the difference between the two answers
    According to the problem, the answer the boy obtained is 200 more than the correct answer. Mathematically, we can express this as:
    45x = 25x + 200

    Step 4: Solve the equation
    To find the value of 'x', we need to solve the equation we obtained in the previous step. Let's simplify it:
    45x - 25x = 200
    20x = 200
    x = 200/20
    x = 10

    Therefore, the number that the boy mistakenly multiplied by 45 instead of 25 is 10. Hence, the correct answer is option 'B'.

    The sum of the squares of three consecutive positive numbers is 365. What will the sum of numbers?
    • a)
      36
    • b)
      33
    • c)
      45
    • d)
      None of the above
    Correct answer is option 'B'. Can you explain this answer?

    Nishant Sethi answered
    Problem Analysis

    We are given that the sum of the squares of three consecutive positive numbers is 365. Let's assume the three consecutive numbers as x, x+1, and x+2.

    Solution

    We can represent the sum of the squares of these three numbers as an equation:
    x^2 + (x+1)^2 + (x+2)^2 = 365

    Expanding the equation:
    x^2 + (x^2 + 2x + 1) + (x^2 + 4x + 4) = 365
    3x^2 + 6x + 5 = 365
    3x^2 + 6x - 360 = 0
    Divide the equation by 3:
    x^2 + 2x - 120 = 0

    Factorizing the Equation

    We need to factorize the quadratic equation x^2 + 2x - 120 = 0 to find the values of x.

    (x + 12)(x - 10) = 0

    From the equation, we have two possible values for x:
    x + 12 = 0 or x - 10 = 0

    If x + 12 = 0, then x = -12, which is not a positive number. Hence, we discard this solution.

    If x - 10 = 0, then x = 10. This gives us the first number as 10.

    Calculating the Other Numbers

    Using the value of x = 10, we can calculate the other two consecutive numbers:
    First number: x = 10
    Second number: x + 1 = 10 + 1 = 11
    Third number: x + 2 = 10 + 2 = 12

    Sum of the Numbers

    The sum of the three numbers is:
    10 + 11 + 12 = 33

    Therefore, the correct answer is option 'B', which is 33.

    What is the decimal equivalent of 111012 ?
    • a)
      3010
    • b)
      2910
    • c)
      2810
    • d)
      2710
    Correct answer is option 'B'. Can you explain this answer?

    Sudhir Patel answered
    Concept:
    The binary number system with only two independent digits, 0 and 1, is a base-2 number system. All larger binary numbers are represented in terms of ‘0’ and ‘1’.
    The decimal number is equal to the sum of binary digits (Dn) times their power of 2 (2n).
    Decimal = - - - + D2 × 22 + D1 × 21 + D0 × 20 - - -
    Calculation:
    Given binary number = 111012
    The equivalent decimal representation will be:
    Decimal = 1 × 24 + 1 × 23 + 1 × 22 + 0 × 21 + 1 × 20
    Decimal = 16 + 8 + 4 + 0 + 1
    Decimal = (29)10

    In sign-magnitude numbers
    • a)
      ms bit always 1
    • b)
      ms bit 0 stands for the positive numbers
    • c)
      ms bit 0 stands for the negative numbers
    • d)
      ms bit 1 stand for the positive numbers
    Correct answer is option 'B'. Can you explain this answer?

    Sudhir Patel answered
    Signed magnitude representation uses the most significant bit (MSB) a sign bit.
    1) If the sign bit is ‘0’ then the number is positive.
    2) If the sign bit is ‘1’ then the number is negative.
    The remaining bits represent the magnitude of the binary number.
    1000101 represents a negative number as the MSB bit is '1'
    0101001 represents a positive number as the MSB bit is '0'

    The difference in the dynamic range of 32-bit binary number(B) and floating-point number(F) is?
    Standard Format for B and F as given below :
    B=

    F=
    • a)
      6.02(27 - 30) dB
    • b)
      6.02(28 - 31) dB
    • c)
      6.02(27 - 31) dB
    • d)
      6.02(28 - 30) dB
    Correct answer is option 'B'. Can you explain this answer?

    Sudhir Patel answered
    Concept:
    The dynamic range in 
    In fixed point, unsigned integer representation using N-bit, the range of Max to Min is 2N to 1
    In fixed-point signed integer representation using N-bit, the range of Max to Min number is 2N-1 to 1
    Calculation:
    The dynamic range of a 32-bit binary number B is:

    Exponent = e – 127 varies from –127 to 128,
    e = 0 = all bits (b30 ---- b23) are zero.
    Now, the dynamic range is determined by the size of the exponent, which is
    1 × 2-127(min) to 2128 (max).
    Dynamic range:

    Difference in Dynamic Ranges = 6.03 (28 – 31)
    So, Option (2) is correct.

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