Nancy made a rectangular prism using clay. The length of the prism is 15 centimeters, the width is 12 centimeters, and the height is 10 centimeters. How much clay did Nancy use to make the prism?

5/8 beds for each square yard

Use pythagorean’s theorem and find the missing side lengths of the two smaller triangles and add them together
13^2 - 12^2 = 5
15^2 - 12^2 = 9
5+9 = 14
14 is the length of each side of the square
14^2 + 14^2 = 19.8
19.8 is the diagonal length of the inside if the square