What is the diameter of a soup can if the lateral surface area is 188.4 square centimeters and the height is 10 centimeters?

Question

I need to use the formula for the surface area of a cylinder to find the diameter, but I'm confused on what to do with pi and the radius?

Answer 1

Using LATERAL SURFACE AREA = 2(pi)(r)(h), and substituting 188.4 for that L.S.A, along with 3.1416 for pi & h = 10 cm, you have and equation with only the unknown value r.

 

In other words, after working out the product of 2, pi and h on the right side, you have some number times r = 188.4

 

Now divide out "some number" and that's r.