Question

A joker's cap is in the form of a right circular cone of base radius 7 cm and height 24cm.
Find the area of the sheet required to make 10 such caps.

Answer 1

radius = 7cm
height = 24 cm

l =√r² +h²
l =√7² + 24²
l = √49 + 576
l = √625
l = 25

Curved surface area of one conical cap =
πrl= (22/7)×(7)×25
= 550 cm ²


Curved surface area of 10 conical caps = 10 × 550 cm ²= 5500 cm²

∴ the area of sheet required to make 10 conical caps is 5500 cm²

Answer 2

as joker's cap is in the form of cone 
radius of cone = 7 cm
height of cone = 24 
slant height of cone = 
l² = r² + h²
l ² = (7) ² + (24) ²
l² = 49 + 576
l² = 625
l = 25

area of sheet required to make 1 cap = Curved surface area of cone 
=πrl 
22 / 7 * 7 * 25
22 *25
550cm² 
sheet required for such 10 caps  = 10 * 550 
                                              = 5500 cm²