# Frank Learning Maths Class 8 Chapter 2 Exponents Chapter Check-up Solutions

## Frank Learning Maths Class 8 Chapter 2 Exponents Chapter Check-up Solutions

This post is created to help all the CBSE Class 8 students for the Solutions of Frank Learning Maths Class 8 Mathematics Book, Chapter 2 Exponents Chapter Check-up. Here students can easily find step by step solutions of all the problems for Exponents Chapter Check-up. Exercise wise proper solutions for every problems. All the problem are solved with easily understandable methods so that all the students can understand easily.

Chapter 2 – Exponents

Exponents – Chapter Check-up all Questions Solution

(1) Fill in the blanks

Solution :

(a) The reciprocal of (2/5)^-1 is – (2/5)

(b) (- 2)^2×3-1 = (- 2)^6-1 = (- 2)^5 = – 3^2

(c) (- 3/4)^5 × (5/3)^5 is equal to – 3^5/4^5 × 5^5/3^5 = (- 5/4)^5

(d) [2^-1 + 3^-1 + 4^-1]^0 = 1

(e) (6^0 – 7^0) (6^0 + 7^0) = (1 – 1) (1 + 1) = 0

(f) The standard form of 0.000064 is 6.4 × 10^-5

(g) The standard form of 234500000 is 2.345 × 10^8

(h) The usual form of 2.03 × 10^-5 is = 0.000203

(i) Cube of – 1/2 is (- 1/2)^3 = – 1/8

(j) The value of [3^-1 × 4^-1]^2 is 1/3 × 1/4 = 1/12

(2) Simplify

Solution :

(a) (1/4)-2 + (1/2)-2 + (1/3) -2

= (4) 2 + (2) 2 + (3)2

= 16 + 4 + 9

= 29…(Simplified)

(b) (-2/3) -2)3 × (1/3)-4 × 3-1 × 1/6

= ((3/2) 23 × (3) 4 × 1/3 × 1/3×2

= (3 × 2/2 × 2) 3 × 32 × 32 × 1/32 × 2

= 33 × 33/23 × 23 × 32/2

= 38/28…(Simplified)

(c) 49 × z-3/7-3 × 10 × z-5 (z ≠ 0)

= 72 × z2/7-3 × 10

= 75 × z2 × 10-1…(Simplified)

(d) (25 ÷ 28) × 2-7

= 25/28 × 2-7

= 2-7/2-3

= 1/24…(Simplified)

(3) Find the value of x so that

Solution :

(a) (5/3) -2 × (5/3) -14 = (5/3) 8x

= (5/3) -16 = (5/3) 8x

= 8x = -16

= x = -2

So, the value of x will be -2

(b) (- 2) 3 × (- 2) -6 = (- 2) 2x – 1

= (- 2) -3 = (- 2) 2x – 1

= 2x -1 = -3

= 2x = -2

= x = -1

Hence, the value of x will be -1

(c) (2-1 + 4-1 + 6-1 + 8-1x = 1

= (2-1 + 4-1 + 6-1 + 8-1x

= (2-1 + 4-1 + 6-1 + 8-10

= x = 0

Therefore, the value of x will be 0.

(4) Express each of the following in standard form

Solution :

(a) The mass of a proton in gram is 1673/1000000000000000000000000000

= 1.673 × 10-24 gram

(b) A Helium atom has a diameter of 0.000000022 cm.

= 2.2 × 10-8 cm

(c) Mass of a molecule of hydrogen gas is about 0.00000000000000000000334 tons.

= 3.34 × 10-22 tons.

(d) Human body has 1 trillion of cells which vary in shapes and sizes.

= 1 × 1012

(e) Express 56 km in m.

= 5.6 × 104 m

(f) Express 5 tons in g.

= 5 × 105 gm

(g) Express 2 years in seconds.

= 6.3072 × 107 s

(h) Express 5 hectares in cm2 (1 hectare = 10000 m2)

= 5 × 108 cm2

(5) Find the value of n

Solution :

(a) 6n/6-2 = 63

= (6) n+2 = 63

= x + 2 = 3

= x = 1

Hence, the value of n will be 1.

(b) 2× 26/2-3 = 218

= 26+n+3 = 218

= n + 9 = 18

= n = 9

Thus, the value of n will be 9.

Question no – (6)

Solution :

As per the given question,

The diameter of the sun = 1.4 × 109 m

The diameter of the earth = 1.2756 × 107 m

1.4 × 109 m

= 1.2756 × 107 m

= 1.3 × 107 m (Approximately)

Therefore, diameter of the sun is 100 time of the Earth diameter.

Question no – (7)

Solution :

According to the question,

Mass of mars is 6.42 × 1029 kg

Mass of the sun is 1.99 × 1030 kg.

6.42 × 1029 kg + 1.99 × 1030

= 6.42 × 1029 + 19.9 × 1029

= 26.32 × 1029

= 2.632 × 1030 kg

Hence, the total mass will be 2.632 × 1030 kg.

Question no – (8)

Solution :

As per the question,

Distance between sun and earth is = 1.496 × 108 km

Distance between earth and moon is = 3.84 × 108 m

∴ Distance between moon and sun,

= – 1.496 × 108/2

= 7.48 × 107

Therefore, the distance between moon and sun will be 7.48 × 107

Question no – (11)

Solution :

According to the question,

The cells of a bacteria double itself every hour.

How many cells will there be after 8 hours,

The answer in power will be 28

Question no – (12)

Solution :

Given, (2/9)3 × (2/9)-6 = (2/9)2x-1

= – 3 = 2x – 1

= 2x = -2

= x = -1

Therefore, the x will be -1

Question no – (13)

Solution :

Let, we should divided the number by x

∴ (- 3/2) -3/x = (4/27) -2

= -(2/3) 3 × 1/x = (27/4) 2

= – (2/3) 3 × (4/27) 2 = x

= – 23/33 × 24/36 = x

= (- 2) 7/39 = x

Therefore, (-2)7/39 should be divided.

Updated: February 2, 2023 — 3:01 pm