Test: Rational Numbers- 1 - Class 8 MCQ

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

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.

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. 

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.

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

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

The rational number 1 is the multiplicative identity for rational numbers because on multiplying any rational number with 1, we get the same number.

-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.

So option A is the correct answer. 

The correct option is C 0
0 is the identity element under addition for the real numbers, since if a is any real number, a + 0 = 0 + a = a.