MCQs on Class 8th math Rational Numbers

1. An integer can be: a) Only Positive b) Only Negative c) Both positive and negative d) None of the above

Answer: (c) Explanation: An integer can be both positive and negative as well as zero.

2. A rational number can be represented in the form of: a) p/q b) pq c) p+q d) p-q

Answer: (a) Explanation: A rational number can be represented in the form p/q where p and q are integers and q is not equal to zero.

3. The value of ½ x ⅗ is equal to: a) ½ b) 3/10 c) ⅗ d) ⅖

Answer: (b) Explanation: ½ x ⅗ = (1×3)/(2×5) = 3/10

4. The value of (½) ÷ (⅗) is equal to: a) 3/10 b) ⅗ c) 6/5 d) ⅚

Answer: (d) Explanation: (½) ÷ (⅗) = (½) x (5/3) = (1×5)/(2×3) = ⅚

5. The value of ½ + ¼ is equal to: a) ¾ b) 3/2 c) ⅔ d) 1

Answer: (a) Explanation: ½ + ¼ Making the denominator equal: 2/4 + ¼ = (2+1)/4 = ¾

6. The value of 5/4 – 8/3 is: a) 17/12 b) -17/12 c) 12/17 d) -12/17

Answer: (b) Explanation: 5/4 – 8/3 Making the denominator equal: [(5/4) x (3/3)] – [(8/3) x (4/4)] 15/12 – 32/12 = (15-32)/12 = -17/127.

The associative property is applicable to: a) Addition and subtraction b) Multiplication and division c) Addition and Multiplication d) Subtraction and Division

Answer: (c) Explanation: As per associative property: A+B = B+A A.B = B.A Where A and B are two integers.

8. The value of (-10/3) x (-15/2) x (17/19) x 0 is: a) 0 b) 22.66 c) 20 d) 35

Answer: (a) Explanation: Any number multiplied by zero is equal to zero.

9. The additive identity of rational numbers is: a) 0 b) 1 c) 2 d) -1

Answer: (a) Explanation: Any number added to zero is equal to the number itself. Ex: 5+0 = 5

10. The multiplicative identity of rational numbers is: a) 0 b) 1 c) 2 d) -1

Answer: (b) Explanation: Any number multiplied by 1 is equal to the number itself Ex: 5 x 1 = 5