Question

a path of 4 m width runs round a semi-circular grassy plot whose circumference is 163 3/7 m
Find:
(i) the area of the path
(ii) the cost of gravelling the path at the rate of 1.50 per m²
(iii) the cost of turfing the plot at the rate of 45 paise per m².

pls solve immediately
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Answer 1

Circumference of plot=

163 7/3m= 7/1144m

⇒2πr=7/1144

⇒r= 7×44/1144×7

=26m

i) Area of path=π(R^2−r^2)= 7/22((26+4)2−(26)^2)

= 7/22×14.97=47.05㎡

ii) Cost of graveling=Rs. (47.05×1.50)=Rs. 70.575

iii) Area of plot=πr2 = 7/22

×26×26=2124.57㎡

Cost of turfing=Rs. (2124.57×0.45)=Rs. 956.06