Question

Curved surface area of a birthday cap (conical shape) is 308 cm2 and its slant

height is 14cm. find radius and height (nearest to whole number)of birthday cap.

(Use

3 = 1.73)
​

Answer 1

Step-by-step explanation:

curved surface area of cone= πrl= 308cm²

=> 22/7*r*14= 308

r= 308*7/22*14 => r= 7 cm

as, (slant height)²=(height)²+(radius)²

=> (14)²=(h)²+(7)²

=> 196 = h² + 49, => h²= 196-49

=> h²= 147, => h=√147

h= 12.12 cm

hence, r= 7 cm, and h= 12.12 cm