SCERT AP 7th Class Maths Solutions Pdf Chapter 8 Exponents and Powers Ex 8.3 Textbook Exercise Questions and Answers.

AP State Syllabus 7th Class Maths Solutions 8th Lesson Exponents and Powers Ex 8.3

Question 1.
Write the following numbers in expanded form.
(i) 23468
Answer:
23468 = (2 × 10,000) + (3 × 1000) + (4 × 100) + (6 × 10) + (8 × 1)
= (2 × 104) + (3 × 103) + (4 × 102) + (6 × 101) + (8 × 1)

(ii) 120718
Answer:
120718 = (1 × 1,00,000) + (2 × 10,000) + (0 × 1000) + (7 × 100) + (1 × 10) + (8 × 1)
= (1 × 105) + (2 × 104) + (7 × 102) + (1 × 101) + (8 × 1)

(iii) 806190
Answer:
806190 = (8 × 1,00,000) + (0 × 10,000) + (6 × 1000) + (1 × 100) + (9 × 10) + (0 × 1)
= (8 × 105) + (6 × 103) + (1 × 102) + (9 × 101)

(iv) 3006194
Answer:
3006194 = (3 × 10,00,000) + (0 × 1,00,000) + (0 × 10,000) + (6 × 1000) + (1 × 100) + (9 × 10) + (4 × 1)
= (3 × 106) + (6 × 103) + (1 × 102) + (9 × 101) + (4 × 1)

AP Board 7th Class Maths Solutions Chapter 8 Exponents and Powers Ex 8.3

Question 2.
Write the following numbers in standard fortti:
(i) 5,00,000
Answer:
5,00,000 = 5 × 1,00,000 = 5 × 105

(ii) 48,30,000
Answer:
48,30,000 = 4.830000 × 10,00,000 (Decimal is shifted six places to the left).
= 4.830000 × 106
∴ 48,30,000 = 4.83 × 106

(iii) 3,94,00,00,00,000
Answer:
3,94,00,00,00,000 = 3.94000000000 × 100000000000 = 3.94 × 1011

(iv) 30000000
Answer:
30000000 = 3 × 10000000 = 3 × 107
∴ 30000000 = 3 × 107

(v) 180000
Answer:
180000 = 1.80000 × 100000 = 1.8 × 105

Question 3.
Express the number appearing in the following statements in standard form,
(i) The Universe is estimated to be about 12,000,000,000 years old.
Answer:
The Universe is 12,000,000,000 years old = 12 × 1,000,000,000
= 12 × 109 years.
= 1.2 × 1010 years.

AP Board 7th Class Maths Solutions Chapter 8 Exponents and Powers Ex 8.3

(ii) Earth circumference is about 402000000 km.
Answer:
Earth circumference = 402000000 km
= 4.02000000 × 100000000 (Decimal is shifted eight places to left)
= 4.02 × 108 km.
∴ Earth circumference = 4.02 × 108 km.