Question 1:
Solution:
Round off each of the following numbers to the number of significant figures indicated in brackets.
(a) 80616 (3 s. f.)
(b) 60932 (3 s. f.)
(c) 0.4783 (2 s. f.)
(d) 3.047 (3 s. f.)
(e) 0.00567 (2 s. f.)
(f) 0.05086 (3 s. f.)
Solution:
(a) 80600
(b) 60900
(c) 0.48
(d) 3.05
(e) 0.0057
(f) 0.0509
Question 2:
Express each of the following as a single numbers.
(a) 8.565 × 10-5
(b) 1.304 × 105
Solution:
Express each of the following as a single numbers.
(a) 8.565 × 10-5
(b) 1.304 × 105
(c) 6.754 × 10-6
(d) 1.0352 × 104
Solution:
(a) 0.00008565
(b) 130400
(c) 0.000006754
(d) 10352Question 3:
Express each of the following in standard form.
(a) 376510
(b) 47865400
(c) 0.000507
(d) 0.00006408
Solution:
Express each of the following in standard form.
(a) 376510
(b) 47865400
(c) 0.000507
(d) 0.00006408
Solution:
(a) 3.7651 × 105
(b) 4.78654 × 107
(c) 5.07 × 10-4
(d) 6.408 × 10-5
Question 4:
Solution:
1.3 × 1015 + 3.2 × 1014
Solution:
1.3 × 1015 + 3.2 × 1014
= 1.3 × 1015 + 0.32 × 1015
= (1.3 +0. 32) × 1015
= 1.62 × 1015
Question 5:
Solution:
0.0000036 – 2.1 × 10-7
Solution:
0.0000036 – 2.1 × 10-7
= 3.6 × 10-6 – 2.1 × 10-7
= 3.6 × 10-6 – 0.21 × 10-6
= (3.6 – 0.21) × 10-6
= 3.39 × 10-6