Q25 of 32 Page 13

Find the Total surface area and volume of a cone whose height is 28 cm and diameter is 42 cm.

Radius = 42 cm ÷ 2 = 21 cm, h = 28 cm
Total surface area = π r (l + r) = × 21 (35 + 21) cm2 = 3696 cm2
Volume of cone = π r2h = × × 21 × 21 × 28 = 12, 936 cm2

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