Question

A radius of the base of a right circular cone having carved surface area 528 CM square and slant height 21 CM will be

Answer 1

$curved \: surface \: area \: of \: cone \: = \pi rl$

$528 = \frac{22}{7} \times 21 \times r$

$528 = 22 \times 3 \times r$

$528 = 66r$

$r = \frac{528}{66}$

$r = 8cm$

$therefore \: radius \: of \: the \: cone \: will \: be \: 8cm$