How much cardboard is required for making 50 pen holders in shape of a cylinder with a base ,if each pen holder is to be of a diameter 2 cm and height 10 cm
Answers
Step-by-step explanation:
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?
r = 3 cm
h = 10.5 cm
∴ Cardboard required for 1 competitor
equals 2 πrh plus πr squared
equals 2 cross times 22 over 7 cross times 3 cross times 10.5 plus 22 over 7 left parenthesis 3 right parenthesis squared
equals space 198 plus 198 over 7 equals 198 open parentheses 1 plus 1 over 7 close parentheses
equals space fraction numerator 198 cross times 8 over denominator 7 end fraction space cm squared
∴ Cardboard required for 35 competitors
equals fraction numerator 198 cross times 8 over denominator 7 end fraction cross times 35 space cm squared equals 7920 space cm squared
Hence, 7920 cm2 of cardboard was required to be bought for the competition.