Question

A file folder box is in the shape of a rectangular prism with a length of 12 inches, a width of 9 inches, and a height of 10 inches. it is open at the top.find the surface area of the folder box

Answer 1

Surface area =  12*9 + 2*12*10 + 2*9*10 =  528  in^2   Answer

(its only one 12*9 because it is open at the top)