Class 8 Maths Chapter 12 Exponents and Powers MCQs

Class 8 Maths Chapter 12 (Exponents and Powers) MCQs are available online for students. These objective questions are designed by experts, according to CBSE syllabus (2020-2021) and NCERT guidelines. The chapter-wise multiple-choice questions are available, to make students learn each concept and lead them to score good marks in exams. Also, learn important questions for class 8 Maths here.

MCQs on Class 8 Exponents and Powers

Multiple choice questions (MCQs) are given for Class 8 Exponents and Powers chapter. Solve each question and choose the right answer.

1. The value of 2^-2 is:

A. 4

B. ¼

C. 2

D. ½

Answer: B

Explanation: 2^-2 = 1/2² = ¼

2. The multiplicative inverse of 7^-2 is:

A. 7²

B. 7

C. 1/7²

D. 1/7

Answer: A

Explanation: The multiplicative inverse of any value is the one which when multiplied by the original value gives a value equal to 1.

7^-2 = 1/7²

Hence, 7² x 1/7² = 1

3. 2² x 2³ x 2⁴ is equal to:

A. 2²⁴

B. 2^-5

C. 2⁹

D. 2^-9

Answer: C

Explanation: By laws of exponents:

a^m x aⁿ = a^m+n

2² x 2³ x 2⁴ = 2²⁺³⁺⁴ = 2⁹

4. 3^-2 x 3^-5 is equal to:

A. 3^-7

B. 3^-3

C. 3^-10

D. 3⁷

Answer: A

Explanation: 3^-2 x 3^-5 = (1/3²) x (1/3⁵)

= (1/3²⁺⁵)

= (1/3⁷)

= 3^-7

5. 5⁴/5² is equal to:

A. 5⁶

B. 5^-6

C. 5^-2

D. 5²

Answer: D

Explanation: By exponent law:

a^m/aⁿ = a^m-n

5⁴/5² = 5^4-2 = 5²

6. The value of (3⁴)³ is:

A. 3

B. 3¹²

C. 3⁷

D. None of the above

Answer: B

Explanation: By law of exponent:

(a^m)ⁿ = a^mn

(3⁴)³ = 3^4×3 = 3¹²

7. 3² x 4² is equal to:

A. 121

B. 49

C. 144

D. 156

Answer: C

Explanation: By exponent law;

a^m x b^m = (ab)^m

3² x 4² = (3×4)² = 12² = 144

8. 5⁷/6⁷ will give the value:

A. (⅚)⁷

B. (⅚)⁰

C. (⅚)^-7

D. (6/5)^-7

Answer: A

Explanation: By exponent law:

a^m/b^m = (a/b)^m

5⁷/6⁷ = (⅚)⁷

9. 100⁰+20⁰+5⁰ is equal to

A. 125

B. 25

C. 1/125

D. 3

Answer: D

Explanation: By exponent law we know:

a⁰ = 1

100⁰ + 20⁰ + 5⁰ = 1+1+1 = 3

10. If (–3)^m+1 × (–3)⁵ = (–3)⁷, then the value of m is:

A. 5

B. 7

C. 1

D. 3

Answer: C

Explanation: (–3)^m+1 × (–3)⁵ = (–3)⁷

(-3)^m+1+5 = (-3)⁷

(-3)^m+6 = (-3)⁷

Since, base are equal on both the sides, hence if we compare the powers,

m+6 = 7

m=7-6 = 1