Mensurationhard · Past Paper
A solid consists of a cylinder with a cone on top and a hemisphere at the bottom. The radius is 7 cm. Height of cylinder is 10 cm and cone is 4 cm. Find the total surface area.
A770 + 7π√65 sq. cm
B748 + 7π√65 sq. cm
C800 sq. cm
DNone of these
✓ Correct Answer: B — 748 + 7π√65 sq. cm
TSA = CSA cone + CSA cylinder + CSA hemi. r=7. l=√(7²+4²)=√65. Area = πrl + 2πrh + 2πr² = π*7*√65 + 2*π*7*10 + 2*π*7² = 7π√65 + 140π + 98π = 7π√65 + 238π.
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