The slant height and base diameter of a conical tomb are 25 m and 14 m respectively. Find the cost of white-washing its curved surface at the rate of Rs. 210 per 100 m2.
We have,
Radius of conical tomb = diameter /2 = 14/2 = 7 m
Slant height = l = 25 m
Curved surface area = πrl
Cost of white washing = (curved surface area × rate of white washing per m2)
= 
= 
= Rs.1155
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