Find the area of the curved surface of a cone whose base radius is 3cm and whose height is 4cm (π = 3.14)
-
A.
17.1cm2 -
B.
27.2cm2 -
C.
47.1cm2 -
D.
37.3cm2
Correct Answer: Option C
Explanation
Find the slant height
( l^2 = h^2 + r^2(h = 4cm,r = 3cm))
( l^2 = 4^2 + 3^2 = 16 + 9 = 25 )
( l^2 = √ 25 )
Squaring both sides
l = 5cm
The area of curved surface (s) =π(3)(5)
15π = 15 × 3.14
= 47.1cm2
There is an explanation video available below.