Question

find the curved surface area of a cone is the diameter of its base is 126 cm and height is 225 CM

Answer 1

Hola

Here is your answer

Given - Diameter of cone - 126cm

Height - 225 cm

To find - Curved Surface area of Cone

Calculation -

C.S.A of cone = πrl

r = d/2 => 126/2 => 63cm

l = Slant height

Slant height =

l= √ r² + √h²

l = √ 63² + √225²

l = √ 3,969 + 50,625

l = 233. 65

therefore,

l = 233.65 cm

C. S. A = πrl

= 22/7 × 63 × 233.65

= 22 × 9 × 233.65

= 198 × 233.65

= 46262.7 cm²

Answer - C.S.A of cone =
46262.7 cm²

Hope it helps!

Answer 2

$curved \: surface \: area \: of \: cone = \pi \: rl \\ where \: l \: is \: slant \: height \: \\ and \: l = \sqrt{ {r}^{2} + {h}^{2} } \\ radius \: of \: \: cone(r) = \frac{126}{2} \: cm \\ 63 \: cm \\ l = \sqrt{ {63}^{2} + {225}^{2} \: {cm}^{2}} \\ l = \sqrt{54594} \\ l= \sqrt{233.65} \\ curved \: surface \: area = \frac{22}{7} \times 63 \times 233.65 \\ = 22 \times 9 \times 233.65 \\ curved \: surface \: area= 46262.7 \: {cm}^{2}$