KSEEB Solutions for Class 7 Maths Chapter 13 Exponents and Powers Ex 13.3

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Students can Download Class 7 Maths Chapter 13 Exponents and Powers Ex 13.3 Questions and Answers, Notes Pdf, KSEEB Solutions for Class 7 Maths helps you to revise the complete Karnataka State Board Syllabus and to clear all their doubts, score well in final exams.

Karnataka State Syllabus Class 7 Maths Chapter 13 Exponents and Powers Ex 13.3

Question 1.
Write the following numbers in the expanded forms:
279404, 3006194, 2806196, 120719, 20068.
Solution:
279404 = 2 × 105 + 7 × 104 + 9 × 103 + 4 × 102 + 0 × 101 + 4 × 100
3006194 = 3 × 106 + 0 × 105 + 0 × 104 + 6 × 103 + 1 × 102 + 9 × 101 + 4 × 100
2806196 = 2 × 106 + 8 × 105 + 0 × 104 + 6 × 103+ 1 × 102 + 9 × 103 + 6 × 100
120719 = 1 × 105 + 2 × 104 + 0 × 103 + 7 × 102 + 1 × 101 + 9 × 100
20068 = 2 × 104 + 0 × 103 + 0 × 102 + 6 × 101 + 8 × 100

KSEEB Solutions for Class 7 Maths Chapter 13 Exponents and Powers Ex 13.3

Question 2.
Find the number from each of the following expanded forms:
a. 8 × 104 + 6 × 103 + 0 × 102 + 4 × 101 + 5 × 100
b. 4 × 105 + 5 × 103 + 3 × 102 + 2 × 100
c. 3 × 104 + 7 × 102 + 5 × 100
d. 9 × 105 + 2 × 102 + 3 × 101
Solution:
a. 86045
b. 405302
c. 30705
d. 900230

Question 3.
Express the following numbers in standard form:
(i) 5,00,00,000
(ii) 70,00,000
(iii) 3,18,65,00,000
(iv) 3,90,878
(v) 39087.8
(vi) 3908.78
Solution:
(i) 5,00,00,000 = 5 × 107
(ii) 70,00,000 = 7 × 106
(iii) 3,18,65,00,000 = 3.1865 × 109
(iv) 3,90,878 = 3.90878 × 105
(v) 39087.8 = 3.90878 × 104
(vi) 3908.78 = 3,90878 × 103

KSEEB Solutions for Class 7 Maths Chapter 13 Exponents and Powers Ex 13.3

Question 4.
Express the number appearing in the following statements in standard form.
(a) The distance between Earth and Moon is 384,000,000 m.
Solution:
3.84 × 108m

(b) Speed of light in vacuum is 300,000,000 m/s.
Solution:
3 × 108m/s

(c) Diameter of the Earth is 1,27,56,000 m.
Solution:
1.2756 × 107m

(d) Diameter of the Sun is 1,400,000,000 m.
Solution:
1.4 × 109m

(e) In a galaxy, there are on average 100,000,000,000 stars.
Solution:
1 × 1011

(f) The universe is estimated to be about 12,000,000,000 years old.
Solution:
1.2 × 1010 years.

(g) The distance of the Sun from the centre of the Milky Way Galaxy is estimated to be 300,000,000, 000,000,000,000 m.
Solution:
3 × 1020m.

(h) 60,230,000,000,000,000,000,000 molecules are contained in a drop of water weighing 1.8 gm.
Solution:
6.023 × 1022

(i) The earth has 1,353,000,000 cubic km of sea water.
Solution:
1.353 × 109 cubic km.

(j) The population of India was about 1,027,000,000 in March, 2001.
Solution:
1.027 × 109.

KSEEB Solutions for Class 7 Maths Chapter 13 Exponents and Powers Ex 13.3