The height of the cone is 12 not 18 correct it you will get the correct answer.
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The slant height and the diameter of a conical tomb are 25 m and 14 m
respectively. Find the cost of constructing it at the rate of ₹ 25 per cubic metre
and cost of white washing its curved surface area at the rate of ₹16 per square metre.
(Use π = 22/7)