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Can you explain the answer of this question below:Practice Quiz or MCQ (Multiple Choice Questions) with solutions are available for Practice, which would help you prepare for chapter Rational Numbers, Class 8, Mathematics . You can practice these practice quizzes as per your speed and improvise the topic.
Q.
Find the reciprocal of -2.
- A:
2
- B:
-2
- C:
- 1/2
- D:
None of these
The answer is C.
Practice Quiz or MCQ (Multiple Choice Questions) with solutions are available for Practice, which would help you prepare for chapter Rational Numbers, Class 8, Mathematics . You can practice these practice quizzes as per your speed and improvise the topic.
Q.
Find the reciprocal of -2.
2
-2
- 1/2
None of these
|
Debolina Iyer answered |
The reciprocal of 2is 1/2 then reciprocal of -2 is -1/2 .
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Write the additive inverse of 4/5.
- a)1
- b)-4/5
- c)4/5
- d)0
Correct answer is option 'B'. Can you explain this answer?
Write the additive inverse of 4/5.
a)
1
b)
-4/5
c)
4/5
d)
0
|
Sagnik Iyer answered |
Additive Inverse of 4/5:
Additive inverse is a number that when added to a given number, gives a sum of zero. For example, the additive inverse of 5 is -5, because 5 + (-5) = 0.
To find the additive inverse of 4/5, we need to find a number that when added to 4/5, gives a sum of zero. Let's call this number x.
4/5 + x = 0
To solve for x, we can subtract 4/5 from both sides of the equation.
x = -4/5
Therefore, the additive inverse of 4/5 is -4/5 (option B).
Additive inverse is a number that when added to a given number, gives a sum of zero. For example, the additive inverse of 5 is -5, because 5 + (-5) = 0.
To find the additive inverse of 4/5, we need to find a number that when added to 4/5, gives a sum of zero. Let's call this number x.
4/5 + x = 0
To solve for x, we can subtract 4/5 from both sides of the equation.
x = -4/5
Therefore, the additive inverse of 4/5 is -4/5 (option B).
Which of the following is the product of (-7/8) and 4/21?
- a)-1/6
- b)12
- c)-63/16
- d)-16/147
Correct answer is option 'A'. Can you explain this answer?
Which of the following is the product of (-7/8) and 4/21?
a)
-1/6
b)
12
c)
-63/16
d)
-16/147
|
Mishti Gupta answered |
-7 / 8 x 4 / 21 = - 1 / 6 - To find the product of two fractions, multiply the numerators together and the denominators together.
- (-7/8) * (4/21) = (-7 * 4) / (8 * 21) = -28 / 168
- Simplifying the fraction by dividing both the numerator and denominator by 4, we get -7 / 42
- Further simplifying by dividing both the numerator and denominator by 7, we get -1 / 6
- Therefore, the correct answer is A: -1/6.
- (-7/8) * (4/21) = (-7 * 4) / (8 * 21) = -28 / 168
- Simplifying the fraction by dividing both the numerator and denominator by 4, we get -7 / 42
- Further simplifying by dividing both the numerator and denominator by 7, we get -1 / 6
- Therefore, the correct answer is A: -1/6.
So option A is the correct answer.
Find the multiplicative inverse of -13.- a)13
- b)-13
- c)-1/13
- d)12
Correct answer is 'C'. Can you explain this answer?
Find the multiplicative inverse of -13.
a)
13
b)
-13
c)
-1/13
d)
12
|
Anita Menon answered |
In order to find the multiplicative inverse of the given number, find the reciprocal of that number.
Here the given number is -13
So the reciprocal of -13 will be -1/13
Here the given number is -13
So the reciprocal of -13 will be -1/13
Therefore, option C is the correct answer.
Which of the following is the identity element under addition?- a)1
- b)-1
- c)0
- d)None of these
Correct answer is option 'C'. Can you explain this answer?
Which of the following is the identity element under addition?
a)
1
b)
-1
c)
0
d)
None of these
|
|
Amit Kumar answered |
Zero is called the identity for the addition of rational numbers.
Example: 2/3 + 0 = 2/3
Example: 2/3 + 0 = 2/3
For any three rational numbers a, b and c, a + (b + c) = __________.- a)(a + b) + c
- b)(a + b) - c
- c)(a - b) + c
- d)(a - b) - c
Correct answer is 'A'. Can you explain this answer?
For any three rational numbers a, b and c, a + (b + c) = __________.
a)
(a + b) + c
b)
(a + b) - c
c)
(a - b) + c
d)
(a - b) - c
|
Geetika Shah answered |
It is the associative property and we know that the rational numbers are associative under addition.
For eg: 5/3 + (3/2 + 1/3) = 7/2;
(5/3 + 3/2) + 1/3 = 7/2
Here, Option 'a' is the correct answer.
For eg: 5/3 + (3/2 + 1/3) = 7/2;
(5/3 + 3/2) + 1/3 = 7/2
Here, Option 'a' is the correct answer.
Therefore, a+(b+c) = (a+b)+c
_____ is the only rational number that is equal to its reciprocal. - a)2
- b)1
- c)1/2
- d)0
Correct answer is option 'B'. Can you explain this answer?
_____ is the only rational number that is equal to its reciprocal.
a)
2
b)
1
c)
1/2
d)
0
|
Pooja Shah answered |
1 because the reciprocal of 1 is 1/1 which is equal to 1.
Which of the following is the reciprocal of the reciprocal of a rational number?- a)-1
- b)1
- c)0
- d)The number itself
Correct answer is option 'D'. Can you explain this answer?
Which of the following is the reciprocal of the reciprocal of a rational number?
a)
-1
b)
1
c)
0
d)
The number itself
|
|
Shail Chatterjee answered |
Reciprocal of a number:
The reciprocal of a number is the fraction obtained by interchanging the numerator and the denominator of the given number.
Reciprocal of a rational number:
A rational number is a number that can be expressed as a ratio of two integers. Therefore, the reciprocal of a rational number is also a rational number. For example, the reciprocal of 2/3 is 3/2, which is also a rational number.
Reciprocal of the reciprocal of a rational number:
To find the reciprocal of the reciprocal of a rational number, we need to take the reciprocal of the given rational number twice. In other words, we need to interchange the numerator and denominator twice. For example, if the given rational number is 2/3, then its reciprocal is 3/2, and the reciprocal of 3/2 is 2/3, which is the original number.
Answer:
Therefore, the reciprocal of the reciprocal of a rational number is the number itself. So, the correct answer is option D.
The reciprocal of a number is the fraction obtained by interchanging the numerator and the denominator of the given number.
Reciprocal of a rational number:
A rational number is a number that can be expressed as a ratio of two integers. Therefore, the reciprocal of a rational number is also a rational number. For example, the reciprocal of 2/3 is 3/2, which is also a rational number.
Reciprocal of the reciprocal of a rational number:
To find the reciprocal of the reciprocal of a rational number, we need to take the reciprocal of the given rational number twice. In other words, we need to interchange the numerator and denominator twice. For example, if the given rational number is 2/3, then its reciprocal is 3/2, and the reciprocal of 3/2 is 2/3, which is the original number.
Answer:
Therefore, the reciprocal of the reciprocal of a rational number is the number itself. So, the correct answer is option D.
_______ are closed under addition.- a)Irrational numbers
- b)Negative numbers
- c)Rational numbers
- d)none of these
Correct answer is option 'C'. Can you explain this answer?
_______ are closed under addition.
a)
Irrational numbers
b)
Negative numbers
c)
Rational numbers
d)
none of these
|
|
Ananya Das answered |
Rational Numbers: This set is closed under addition, subtraction, multiplication, and division (with the exception of division by 0).
Which of the following is the Multiplicative identity for rational numbers?- a)1
- b)-1
- c)0
- d)None of these
Correct answer is option 'A'. Can you explain this answer?
Which of the following is the Multiplicative identity for rational numbers?
a)
1
b)
-1
c)
0
d)
None of these
|
|
Geetika Shah answered |
1 is the multiplicative identity for rational numbers, natural numbers, integers.
Find a rational number between 1/4 and 1/2.
- a)2
- b)1/2
- c)3/8
- d)0
Correct answer is option 'C'. Can you explain this answer?
Find a rational number between 1/4 and 1/2.
a)
2
b)
1/2
c)
3/8
d)
0
|
|
Amit Sharma answered |
A rational number between a and b is (a + b)/2
clearly it is there half so it will be between them
where a and b are numbers
a = 1/4, b = 1/2
Therefore, rational no. between 1/4 and 1/2 is
= (1/4 + 1/2)/2
= [(1 + 2)/4]/2
= 3/8
clearly it is there half so it will be between them
where a and b are numbers
a = 1/4, b = 1/2
Therefore, rational no. between 1/4 and 1/2 is
= (1/4 + 1/2)/2
= [(1 + 2)/4]/2
= 3/8
Which of the following is the reciprocal of the reciprocal of a rational number?
- a)2
- b)0
- c)The number itself
- d)None of these
Correct answer is option 'C'. Can you explain this answer?
Which of the following is the reciprocal of the reciprocal of a rational number?
a)
2
b)
0
c)
The number itself
d)
None of these
|
|
Pooja Shah answered |
The reciprocal of the reciprocal of a rational number is the number itself.
For example, Consider the rational no. 3/2. It's reciprocal is 2/3 and the reciprocal of 2/3 is 3/2. Therefore, it's the number itself.
For example, Consider the rational no. 3/2. It's reciprocal is 2/3 and the reciprocal of 2/3 is 3/2. Therefore, it's the number itself.
Zero has ________ reciprocal.
- a)1
- b)2
- c)no
- d)3
Correct answer is option 'C'. Can you explain this answer?
Zero has ________ reciprocal.
a)
1
b)
2
c)
no
d)
3
|
Akshay Mehra answered |
Zero has no reciprocal. Because 1/0 is not defined and also remember any number multiplied by zero gives 0. Therefore, if reciprocal was supposed to be there then that reciprocal when multiplied by 0 should give 1 which is not possible.
Find the multiplicative inverse of 1/4.- a)4
- b)-1/4
- c)-4
- d)1/4
Correct answer is option 'A'. Can you explain this answer?
Find the multiplicative inverse of 1/4.
a)
4
b)
-1/4
c)
-4
d)
1/4
|
Urvashi Sharma answered |
In multiplicative inverse we reciprocal the numbers by which we get the answer =1 that's why 1/4×4/1 which we consider as 4 so 4 is the multiplicative inverse of 1/4
A number which can be written in the form, p/q where p and q are integers and _____ is called a rational number.
- a)q = 0
- b)q ≠ 0
- c)q = 1
- d)none of these
Correct answer is option 'B'. Can you explain this answer?
A number which can be written in the form, p/q where p and q are integers and _____ is called a rational number.
a)
q = 0
b)
q ≠ 0
c)
q = 1
d)
none of these
|
|
Pooja Shah answered |
Given, A rational number is defined as a number that can be expressed in the form p/q , where p and q are integers
We have to find the condition that satisfies the definition.
A number that can be expressed in the form p/q , where p and q are integers and q ≠ 0, is called a rational number.
Therefore, the condition that satisfies the definition is q ≠ 0
A Which of the following statements is true?- a)Every fraction is a rational number.
- b)Every rational number is a fraction.
- c)Every integer is a rational number.
- d)Both (a) and (c).
Correct answer is option 'D'. Can you explain this answer?
A Which of the following statements is true?
a)
Every fraction is a rational number.
b)
Every rational number is a fraction.
c)
Every integer is a rational number.
d)
Both (a) and (c).
|
Shubham Sharma answered |
Every rational number is not a fraction.
In rational numbers, we use integers and in fractions, we use only natural numbers.
In rational numbers, we use integers and in fractions, we use only natural numbers.
________ are closed under subtraction.
- a)Irrational numbers
- b)Negative numbers
- c)Rational number
- d)none of these
Correct answer is option 'C'. Can you explain this answer?
________ are closed under subtraction.
a)
Irrational numbers
b)
Negative numbers
c)
Rational number
d)
none of these
|
|
Amit Sharma answered |
Rational numbers are closed under subtraction.Because if we subtract a rational number with another rational number we will get rational number. For example 45−35 = 10, which is also a rational number.
Correct option is C.
Correct option is C.
Find the multiplicative inverse of 2/9 .- a)-9/2
- b)9/2
- c)-2/9
- d)2/9
Correct answer is option 'B'. Can you explain this answer?
Find the multiplicative inverse of 2/9 .
a)
-9/2
b)
9/2
c)
-2/9
d)
2/9
|
Rohit Sharma answered |
Multiplicative inverse is nothing but a reciprocal of a number 2/9 which is 9/2.
1 is the __________ for rational numbers.- a)multiplicative identity
- b)Addition of zero
- c)additive identity
- d)none of these
Correct answer is option 'A'. Can you explain this answer?
1 is the __________ for rational numbers.
a)
multiplicative identity
b)
Addition of zero
c)
additive identity
d)
none of these
|
|
Geetika Shah answered |
If you multiply any number with 1,the product will always be the same number which you multiply with 1. Therefore, 1 is the multiplicative identity.
Which of the following is the reciprocal of the reciprocal of a rational number?- a) -1
- b) 1
- c) 0
- d)The number itself
Correct answer is option 'D'. Can you explain this answer?
Which of the following is the reciprocal of the reciprocal of a rational number?
a)
-1
b)
1
c)
0
d)
The number itself
|
|
Pooja Shah answered |
1 is the Multiplicative identity for rational numbers.
Practice Quiz or MCQ (Multiple Choice Questions) with solutions are available for Practice, which would help you prepare for chapter Rational Numbers, Class 8, Mathematics . You can practice these practice quizzes as per your speed and improvise the topic.Q.Find the reciprocal of -2.- a)2
- b)-2
- c)- 1/2
- d)None of these
Correct answer is 'C'. Can you explain this answer?
Practice Quiz or MCQ (Multiple Choice Questions) with solutions are available for Practice, which would help you prepare for chapter Rational Numbers, Class 8, Mathematics . You can practice these practice quizzes as per your speed and improvise the topic.
Q.
Find the reciprocal of -2.
a)
2
b)
-2
c)
- 1/2
d)
None of these
|
|
Geetika Shah answered |
reciprocal means interchanging numerator and denominator here it's-2/1 understand after reciprocal denominator came upside so, it will be -1/2
What number should be subtracted from -1 so as to get 5/3?
- a)-8/3
- b)1/4
- c)1
- d)-3/4
Correct answer is option 'A'. Can you explain this answer?
What number should be subtracted from -1 so as to get 5/3?
a)
-8/3
b)
1/4
c)
1
d)
-3/4
|
|
Ananya Das answered |
To find the number that should be subtracted from -1 to get 5/3, we need to perform the following calculation:
-1 - x = 5/3
To isolate x, we can rearrange the equation:
x = -1 - 5/3
To simplify the right side of the equation, we need to find a common denominator:
x = -3/3 - 5/3 x = (-3 - 5)/3
x = -8/3
Therefore, the number that should be subtracted from -1 to get 5/3 is -8/3. Thus, option 1 is the correct answer.
Compare 
- a)
- b)
- c)
- d)
Correct answer is option 'D'. Can you explain this answer?
Compare
a)
b)
c)
d)
|
|
Shubham Sharma answered |
Expressing in standard form, we get 
Express each rational number with L.C.M as denominator. L.C.M of 9 and 5 is 9×5 = 45.
Express each rational number with L.C.M as denominator. L.C.M of 9 and 5 is 9×5 = 45.
Comparing the numerators, we have
−40 <−36.
∴ 
Find the multiplicative inverse of -13.- a)13
- b)-13
- c)-1/13
- d)12
Correct answer is option 'C'. Can you explain this answer?
Find the multiplicative inverse of -13.
a)
13
b)
-13
c)
-1/13
d)
12
|
Kavya Saxena answered |
In order to find the multiplicative inverse of the given number, find the reciprocal of that number.
Here the given number is -13
So the reciprocal of -13 will be -1/13
Here the given number is -13
So the reciprocal of -13 will be -1/13
Therefore, option C is the correct answer.
The product of two rational numbers is always a _______.- a)irrational number
- b)negative number
- c)rational number
- d)None of these
Correct answer is option 'C'. Can you explain this answer?
The product of two rational numbers is always a _______.
a)
irrational number
b)
negative number
c)
rational number
d)
None of these
|
|
Kavya Saxena answered |
Product of two rational numbers is always a rational number.
For example, 1/2 + 1/2 = 1
For example, 1/2 + 1/2 = 1
Practice Quiz or MCQ (Multiple Choice Questions) with solutions are available for Practice, which would help you prepare for chapter Rational Numbers, Class 8, Mathematics . You can practice these practice quizzes as per your speed and improvise the topic.Q.Find the reciprocal of -2.- a)2
- b)-2
- c)- 1/2
- d)None of these
Correct answer is option 'C'. Can you explain this answer?
Practice Quiz or MCQ (Multiple Choice Questions) with solutions are available for Practice, which would help you prepare for chapter Rational Numbers, Class 8, Mathematics . You can practice these practice quizzes as per your speed and improvise the topic.
Q.
Find the reciprocal of -2.
a)
2
b)
-2
c)
- 1/2
d)
None of these
|
Sanjana Bose answered |
The reciprocal of a number is this fraction flipped upside down. In other words, the reciprocal has the original fraction's bottom number—or denominator—on top and the top number—or numerator—on the bottom. So, reciprocal of -2 is -1/2.
Which of the following rational number is its own reciprocal?
- a)-1
- b)1
- c)π
- d)Both a and b.
Correct answer is option 'D'. Can you explain this answer?
Which of the following rational number is its own reciprocal?
a)
-1
b)
1
c)
π
d)
Both a and b.
|
|
Ananya Das answered |
1 and -1 are the only rational numbers which are their own reciprocal. No other rational number is equal to its own reciprocal. So the rational numbers that are equal to their reciprocals are 1 and -1. Note: There is no rational number which when multiplied with zero, gives 1.
________ is not associative for rational numbers.- a)Subtraction or Division
- b)Addition or Multiplication
- c)Addition or Division
- d)Multiplication or Division
Correct answer is option 'A'. Can you explain this answer?
________ is not associative for rational numbers.
a)
Subtraction or Division
b)
Addition or Multiplication
c)
Addition or Division
d)
Multiplication or Division
|
|
Amit Sharma answered |
This is how associative property works. It states that you can add or multiply numbers regardless of how they are grouped. Addition and multiplication are associative for rational numbers. Subtraction and division are not associative for rational numbers.
Which of the following forms a pair of equivalent rational numbers?
- a)24/40 and 35/50
- b)-25/35 and 55/-77
- c)-8/15 and -24/48
- d)9/72 and -3/21
Correct answer is option 'B'. Can you explain this answer?
Which of the following forms a pair of equivalent rational numbers?
a)
24/40 and 35/50
b)
-25/35 and 55/-77
c)
-8/15 and -24/48
d)
9/72 and -3/21
|
|
Ananya Das answered |
When we have to compare two rational numbers, we first make their denominators equal and then compare their numerators.
Similarly, on checking the remaining options we find that -25/35 and 55/-77 is the only pair of equivalent rational numbers.
The value of ½ + ¼ is equal to:- a)⅔
- b)3/2
- c)¾
- d)1
Correct answer is option 'C'. Can you explain this answer?
The value of ½ + ¼ is equal to:
a)
⅔
b)
3/2
c)
¾
d)
1
|
|
Maya Rane answered |
Calculation:
To find the value of ½ + ¼, we need to first convert the fractions to have a common denominator. In this case, the common denominator is 4.
Step 1: Convert ½ to have a denominator of 4:
½ = &frac{2}{2} = &frac{2 \times 2}{2 \times 2} = &frac{4}{4} = &frac{4}{4}
Step 2: Add the two fractions with the common denominator:
¼ + ¼ = &frac{4}{4} + &frac{1}{4} = &frac{4+1}{4} = &frac{5}{4} = 1 ¼
Therefore, ½ + ¼ = 1 ¼, which is the same as ¾.
So, the correct answer is option C - ¾.
To find the value of ½ + ¼, we need to first convert the fractions to have a common denominator. In this case, the common denominator is 4.
Step 1: Convert ½ to have a denominator of 4:
½ = &frac{2}{2} = &frac{2 \times 2}{2 \times 2} = &frac{4}{4} = &frac{4}{4}
Step 2: Add the two fractions with the common denominator:
¼ + ¼ = &frac{4}{4} + &frac{1}{4} = &frac{4+1}{4} = &frac{5}{4} = 1 ¼
Therefore, ½ + ¼ = 1 ¼, which is the same as ¾.
So, the correct answer is option C - ¾.
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