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Probability

Question
CBSEENMA9003394

It is required to make a closed cylindrical tank of height 1 m and base diameter 140 cm from a metal sheet. How many square metres of the sheet are required for the same?

Solution

h = 1 m = 100 cm
2r = 140 cm
rightwards double arrow space space space space space space space straight r equals 140 over 2 space cm space equals space 70 space cm
Total surface area of the closed cylindrical tank = 2πr(h + r)
equals 2 space cross times space 22 over 7 cross times 70 left parenthesis 100 plus 70 right parenthesis
equals space 74800 space cm squared equals fraction numerator 74800 over denominator 100 cross times 100 end fraction space straight m squared
equals space 7.48 space straight m squared

Hence, 7.48 square metres of the sheet are required.