The radius of the base of a conical tent is 8 m and its height is 15 m. What is the cost of the material needed to make it, if it costs Rs.54 per π m2 ?
Answer & explanation
Correct answer: option 2
Slant height of the cone (l) = \(\sqrt{r^2+ h^2}\) = \(\sqrt{8^2 + 15^2}\) = 17
Curved Surface area of cone = πrl
= π x 8 x 17 m2 = 136π m2
⇒ Cost of covering 1π m2 = Rs.54
⇒ Cost of covering 136π m2 = 54 x 136 = Rs.7344