The area of the canvas cloth needed to erect a right conical tent of height 20ft. and circular base of circumference 30π ft. is:
Show answer & explanation
Correct answer: A
Explanation
The correct answer is option 1 i.e. 375π sq.ft.
Find the radius of the base:
Circumference = 2πr
⇒ 30π = 2πr
⇒ r = 15 ft
Find the slant height (l) of the cone:
⇒ l = √(r² + h²)
⇒ l = √(15² + 20²)
⇒ l = √(225 + 400)
⇒ l = √625
⇒ l = 25 ft
Calculate the curved surface area (A) of the cone:
A = πrl
⇒ A = π × 15 × 25
⇒ A = 375π sq ft
Therefore, the area of the canvas cloth needed is 375π square feet.