Question

9. The radii of the circular ends of a frustum of cone of height 6cm are 14cm and 6cm respectively. Find the lateral surface area and total surface area of the frustum.

Answer 1

LSA=628.57,TSA=992.24

R=14.r=6 . h=6 here is only the height is given we need to find (l),.l= √h²+(√R-r)², 36+(14-6)²= √100=10.therefore l = 10 , LSA of frustum=πl(R+r). 22/7×10(14+6)= 628.57. TSA of a frustum = π{R²+r²+Rr}= 992.24