Question

Find the curved surface area and the total surface area of a right circular cylinder whose height is 15 cm and the diameter of the cross-section is 14 cm.

Answer 1

Diameter of the base of cylinder = 14 cm
Radius (r) = 14/2 cm = 7 cm
Height (h) = 15 cm

Curved surface area = 2πrh
= `2 xx 22/7 xx 7 xx 15` = 660 cm²
Total surface area = 2πr (h + r)
= `2 xx 22/7 xx 7(15 + 7)`
= `2 xx 22/7 xx 7 xx 22` = 968 cm²