Find the total surface area of solid circular cone with base radius 3cm and slant height 4cm. [Take \pi = 22/7]
A
37 5/7cm2
B
66cm2
C
75 3/7cm2
D
78 2/7cm2
E
88cm2
Verified Correct Answer: B.
Step-by-Step Mathematical Solution
T.S.A of a cone = \(\pi r^2 + \pi rl\)
= \(\frac{22}{7} \times 3^2 + \frac{22}{7} \times 3 \times 4\)
= \(\frac{198}{7} + \frac{264}{7}\)
= \(\frac{462}{7}\)
= 66 cm\(^2\)
Source: Myschool Past Questions Archive (Record #23742)