Learn Class 7 Math - Exponents and Powers

The term exponents refer to the expanded form of a number, such as 2 x 2 x 2 x 2. At the same time, power refers to a short version of that expanded form, such as 2^4. This whole expression,i.e., 2^4, is called the power.

Rules of Exponents

The rule of exponents differs from each other. These set of rules are discussed here below:

  • a^0 = 1 :

    This rule shows that if the power of the integer is 0, then the result will always come to 1.

  • (a^m)^n = a^mn :

    This set of rules says that if n is the power of a^m and then m is the power of a, the result will be that the product of mn is the power of a.

  • (a^m) x (b^m) = (ab)^m :

    A rule says that if m is the power of both a & b in multiplication, then it is equal to the product of the combination of ab and whose combined power is m.

  • a^m / b^m = (a/b)^m :

    The rule says that if m is the power of both a & b differently, it will result in the combined power of both a & b,i.e.,(a/b)^m.

Exponents and Powers Sample Questions for Class 7

Question 1

121/289 = (x/y)². What is value of x and y?
A. x = 11 , y = 13
B. x = 19, y = 13
C. x = 11, y = 17
D. x = 13, Y = 17

Question 2

What is the value of : ( 2⁰ - 3⁰) 5⁰ ÷ (2⁰ + 3⁰) 5⁰
A. 0
B. 1
C. 3
D. None of the above

Question 3

Raghu was asked to multiply 4 by 2 instead he solved 2⁴. What is the difference between original answer and new answer?
A. 4
B. 8
C. 2
D. 0

Question 4

What is the vaule of x : (2² × 2⁵)÷ ( 2⁸ ÷ 2⁵) = x
A. 4
B. 2³
C. 4²
D. 2²

Question 5

Express in the standard form 1236500000
A. 1.2365× 10⁹
B. 12365× 10⁹
C. 1.23650 × 10⁹
D. 123650 × 10⁹