Question

3. The ratio of radius and slant height of a cone is 4:7. Its lateral sur-
face area is 847 sq.cm. Find the radius of the cone ?
a circle of dis 12 centimetre​

Answer 1

Answer:

Let radius be 4p and slant height be 7p

Lateral surface area of cone =(22/7)rl

(22/7)×4p×7p =847

p^2=847/(22×4)

p^2=77/8=9.625

p=3.1

radius=4×p=12.4 Ans