Find the total surface area of a solid circular cone with base radius 3 cm and slant height 4 cm. [Take \pi = \(\frac{22}{7}\)]
A
66 cm\(^2\)
B
37\(\frac{5}{7}\)cm\(^2\)
C
75\(\frac{3}{7}\)cm\(^2\)
D
78\(\frac{6}{7}\)cm\(^2\)
Verified Correct Answer: A.
Step-by-Step Mathematical Solution
Total surface area of cone = \pirl + \pir\(^2\) = \pir(l + r) r = 3 and l = 4
Area = \(\frac{22}{7}\) \times 3 (4 + 3) = \(\frac{22}{7}\) \times 3 \times 7 = 66 cm\(^2\)
Source: Myschool Past Questions Archive (Record #75836)