Geometry: cylinder object

Question

A cylindrical object is 5 cm tall and has a surface area 10√ 3pi + 6pi cm, including top and bottom. What is approximates the volume of the object in cubic centimeters?

Answer 1

Hi Jaina Y.,

So what do you need to efficiently figure the vouem of a cylinder? Height (which you have) and radius, right?

But you don't know the radius, right off.

So, [do what you should always do when transforming a word problem, which you can't visualize, into a math equation, which you know how to solve!] : set up an expression for surface area, with r as the radius of the cylinder (this is your unknown, or variable). That will be an expression in r , r ^2, and constants. Equate that to the given surface area, and solve for r . The rest should be easy.

-- Cheers, -- Mr. d.