# KSEEB Solutions for Class 8 Maths Chapter 12 Exponents and Powers InText Questions

You can Download KSEEB Solutions for Class 8 Maths Chapter 12 Exponents and Powers InText Questions and Answers helps you to revise the complete syllabus.

## KSEEB Solutions for Class 8 Maths Chapter 12 Exponents and Powers InText Questions

Try These (Page 194)

Question 1.
Find the multiplicative inverse of the following:
(i) 2-4
(ii) 10-5
(iii) 7-2
(iv) 5-3
(v) 10-100
Solution:
(i) Multiplicative inverse of 2-4 is 24.
(ii) Multiplicative inverse of 10-5 is 105.
(iii) Multiplicative inverse of 7-2 is 72.
(iii) Multiplicative inverse of 5-3 is 53.
(iv) Multiplicative inverse of 10-100 is 10100.

Try These (Page 194)

Question 1.
Expand the following numbers using exponents.
(i) 1025.63
(ii) 1256.249
Solution:
(i) 1025.63
= 1000 + 20 + 5 + $$\frac{6}{10}+\frac{3}{100}$$
= 1 × 103 + 2 × 10 + 5 × 1 + $$\frac{6}{10}+\frac{3}{100}$$
= 1 × 103 + 2 × 10 + 5 × 1 + 6 × 10-1 + 3 × 10-2

(ii) 1256.249
= 1000 + 200 + 50 + 6 + $$\frac{2}{10}+\frac{4}{100}+\frac{9}{1000}$$
= 1 × 103 + 2 × 102 + 5 × 10 + 6 × 1 + 2 × 10-1 + 4 × 10-2 + 9 × 10-3

Try These (Page 195)

Question 1.
Simplify and write in exponential form:
(i) (-2)-3 × (-2)-4
(ii) p3 × p-10
(iii) 32 × 3-5 × 36
Solution:
(i) (-2)-3 × (-2)-4
= (-2)3+(-4)
= (-2)-3-4
= (-2)-7
= $$\frac{1}{-2^{7}}$$

(ii) p3 × 10-10
= p3+(-10)
= p3-10
= p-7
= $$\frac{1}{p^{7}}$$

(iii) 32 × 3-5 × 36
= 32-5+6
= 3-3+6
= 33

Try These (Page 199)

Question 1.
Write the following numbers in standard form.
(i) 0.000000564
(ii) 0.0000021
(iii) 21600000
(iv) 15240000
Solution:
(i) 0.000000564 = 5.64 × 10-7
(ii) 0.0000021 = 2.1 × 10-6
(iii) 21600000 = 2.16 × 107
(iv) 15240000 = 1.524 × 107

Question 2.
Write all the facts given in the standard form.
Solution:
All the facts given in the standard form are as under:

1. The distance from the Earth to the Sun is 149,600,000,000 m is 1.496 × 1011 m.
2. The speed of the light is 300,000,000 m/s = 3.00 × 108 m/s.
3. The thickness of the class VII Mathematics book is 20 mm = 2.0 × 10 mm.
4. The average diameter of a Red Blood Cell is 0.000007 mm = 7 × 10-6 mm.
5. The thickness of human hair is in the range of 0.005 cm to 0.01 cm = 5 × 10-3 cm to 1 × 10-2 cm.
6. The distance of the Moon from the Earth is 384,467,000 m (approx) = 3.84467 × 108 m.
7. The size of a plant cell is 0.00001275 m = 1.275 × 10-5 m.
8. The average radius of the Sun is 695000 km = 6.95 × 105 km.
9. The mass of propellant in a space shuttle solid rocket booster is 503600 kg = 5.036 × 105 kg.
10. The thickness of the piece of paper is 0.0016 cm = 1.6 × 10-3 cm.
11. The diameter of a wire on a computer chip is 0.000003 m = 3 × 10-6 m.
12. The height of Mount Everest is 8848 m = 8.848 × 103 m.