Question

The students of a Vidyalaya were asked to participate in a competition for making and decorating penholders in the shape of a cylinder with a base, using cardboard. Each penholder was to be of radius 3 cm and height 10.5 cm. The Vidyalaya was to supply the competitors with cardboard. If there were 35 competitors, how much cardboard was required to be bought for the competition?  [ Assume π = 22/7 ]

Answer 1

Radius (r) of the circular end of cylindrical penholder = 3 cm Height (h) of penholder = 10.5 cm

Surface area of 1 penholder = CSA of penholder + Area of base of penholder = 2πrh + πr²

Area of cardboard sheet used by 1 competitor = 1584/7 cm²

Area of cardboard sheet used by 35 competitors 

= (1584/7 x 35) cm²

= 7920 cm²

 Therefore, 7920 cm² cardboard sheet will be bought.