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?
Given:
R=3cm, H=10.5cm⇒Surface area = Curved Surface Area + Base Area
=2πrh+πr2
=2×227×3×10.510+227×3×3cm2
=198+1987cm2
=15847cm2
⇒Area of cardboard sheet used by competitor =15847cm2
⇒Area of cardboard sheet used by 35 competitors =15847×35
=7920cm2