How do I find the diameter and radius

I need to find the diameter/radius of a soup can using the height (5 inches) and length (10 inches) of a rectangular label on the can.

Supposing the label covers the can completely without overlapping, the 10-inch measurement represents the circumference of the cross-section of the circular can.
So:
πd = 10 inches
d = 10/π inches
r = d/2 = 5/π inches

You know that circumference is Dpi. and using 3.14 for pi plug in what you know.
D(3.14)=10
10/3.14=3.18

so the diameter of the can is 3.18 inches.

The rectangular label's length represents the circumference of the cylindrical can. Use the equation for circumference to solve for the radius, r.

C = 2πr
10 = 2πr
r = 5/π inches

Take the label.and make it into a circle like.it was on the can measure the.circle it makes on th end thru the center from one side to the other is the.diameter split that number in half and its the.radius

8 in. =D
4 in. =R