Test: Rational Numbers- 1


10 Questions MCQ Test Mathematics (Maths) Class 8 | Test: Rational Numbers- 1


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This mock test of Test: Rational Numbers- 1 for Class 8 helps you for every Class 8 entrance exam. This contains 10 Multiple Choice Questions for Class 8 Test: Rational Numbers- 1 (mcq) to study with solutions a complete question bank. The solved questions answers in this Test: Rational Numbers- 1 quiz give you a good mix of easy questions and tough questions. Class 8 students definitely take this Test: Rational Numbers- 1 exercise for a better result in the exam. You can find other Test: Rational Numbers- 1 extra questions, long questions & short questions for Class 8 on EduRev as well by searching above.
QUESTION: 1

Find the reciprocal of -2.

Solution:

reciprocal means interchanging numerator and denominator here it's-2/1 understand after reciprocal denominator came upside so, it will be -1/2 

QUESTION: 2

Which of the following is the reciprocal of the reciprocal of a rational number?

Solution:

The reciprocal of the reciprocal of a rational number is the number itself.
For example, Consider the rational no. 1/2. It's reciprocal is 2 and the reciprocal of 2 is 1/2. Therefore, it's the number itself.

QUESTION: 3

What is the additive inverse of -2/3?

Solution:

Additive inverse of a number is the number who when added to initial number sums up to zero.

If x is a negative number, then its additive inverse is equal and opposite in sign to it. This means that the additive inverse of a negative number is positive.

Hence, additive inverse of -2/3 is 2/3

So option C is the correct answer. 

QUESTION: 4

Find the multiplicative inverse of -13.

Solution:

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

Therefore, option C is the correct answer. 

 

QUESTION: 5

Which of the following is the reciprocal of a rational number?

Solution:

Clearly, we can see that -1 and 1 are the numbers whose reciprocal is the number itself.

QUESTION: 6

Which of the following statements is true?

Solution:

Every rational number is not a fraction.
In rational numbers, we use integers and in fractions, we use only natural numbers.

QUESTION: 7

For any three rational numbers a, b and c, a + (b + c) = __________.

Solution:

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.

Therefore, a+(b+c) = (a+b)+c

QUESTION: 8

Which of the following is the Multiplicative identity for rational numbers?

Solution:

1 is the multiplicative identity for rational numbers, natural numbers, integers.

QUESTION: 9

Which of the following is the product of (-7/8) and 4/21?

Solution:

-7 / 8 x 4 / 21 = - 1 / 6 

So option A is the correct answer. 

QUESTION: 10

Which of the following is the identity element under addition?

Solution:

Zero is called the identity for the addition of rational numbers.
Example: 2/3 + 0 = 2/3