Q13 of 24 Page 227

If the slant height of a right circular cone is 15 cm. and the length of the base diameter is 16cm, then the lateral surface area of the cone is

Slant height, l = 15 cm


Base diameter = 16 cm


∴ base radius, r = 16/2 = 8 cm


∴ lateral surface area of cone,


= πrl


= π × 8 × 15


= 120π cm2

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