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?
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
= [2 * 
* 3 * 10.5 + 
* (3)2] cm2
= (132 * 1.5 + 
) cm2
= (198 + 
) cm2
= 
cm2
Area of cardboard sheet used by 1 competitor = 
cm2
Area of cardboard sheet used by 35 competitors
= 
* 35
= 7920 cm2
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