Question

the radii of circular ends of a bucket in the form of frustum of a cone of height 15cm , are 14cm and rcm. if the capacity of the bucket is 5390cm^3, find r

Answer 1

Volume of frustum = πh/3(R^2+ r^2+R.r)

5390 =22×15/7×3(14^2+r^2+14.r)

5390×3×7/22×15 = 196+ r^2 +14.r

49×7 =196 +r^2+14.r

343-196= r^2 +14r

147 = r^2+14.r

r^2+14r-147=0

r^2+21r-7r-147=0

r(r+21) -7(r+21)=0

(r+21)(r-7)=0

r=-21 / r=7

Ans is 7 because radius not be negative

Answer 2

Here's the answer buddy