# james has a metal frame with an 8.32 inch perimeter. If the sides are 0.04 inches thick, what is the perimeter of the inside of the frame?

0.04 x 4 + .16

8.32 - .16 = 8.16

But the book gives an answer of 8.

I am not sure what I am doing wrong. Can any one help me out. The book doesn't explain the answer.