Question

What is the surface area of a cone with a diameter of 28 cm. and height 22 cm in terms of Ï.

Answer 1

To find the surface area of a cone, use this formula.

pi (r) (r + [square root of h^2 plus r^2] )        substitute

h = height = 22                  r = radius = 28/2 = 14      [ ] = sq. root

pi (14) (14 + [ 22^2 + 14^2 ])                        solve exponents

pi (14) (14 + [484 + 196])                             add

pi (14) (14 + [680])                                       solve square root

pi (14) (14 + 2[170])                                     add

pi (14) (40.0768)                                         multiply

pi (561.075)  is about 561.1 rounded to nearest tenth

So the answer is C. 561.1pi cm^2