a steel drum in the shape of a right circular cylinder is required to have a volume of 100 cu. ft.

Question

express amount A of material needed to make the drum as a function of the radius (r); how much for r=3 ft.; r=4 ft; and r=5ft.

Answer 1

for r=3, base area=pi*3*3=28.2743

hite=100/28.7473=3.53678

surfus area=2 end peeses+side

=2*28.2743+[2*pi*r*hite]

=56.5486+(2*3.14159*3*3.53678)

=56.5486+66.6666)

=123.215