(i) Given radius r = 15 cm
∴ diameter d = 2 x 15
= 30 cm
Circumference C = πd units
= \(\frac{22}{7}\) x 30
= \(\frac{660}{7}\)
= 94.28 cm
(ii) Given circumference C = 1760 cm
2πr = 1760
2 x \(\frac{22}{7}\) x r = 1760
r = \(\frac{1760\times7}{2\times22}\)
= \(\frac{160\times7}{2\times2}\)
= 40 x 7
= 280 cm
Diameter = 2 x r
= 2 x 280
= 560 cm
(iii) diameter d = 24m
radius r = \(\frac{d}{2}\)
= \(\frac{24}{2}\)
= 12 m
Circumference C = 2 πr units
= 2 x \(\frac{22}{7}\) x 12
= \(\frac{528}{7}\)
= 75.4 m
Tabulating the results
| S. No. |
radius (r) |
diameter (d) |
circumference (C) |
| (i) |
15 cm |
30 cm |
94.28 cm |
| (ii) |
280 cm |
560 cm |
1760 cm |
| (iii) |
12 m |
24 m |
75.42 m |
