Math help really important please!?

Question

Betty packages her homemade cookies in a box that is 3 inches wide, 12 inches long, and 6 inches tall. how many square inches of material is needed to make the box that contains her cookies?

Answer 1

There are six sides to this box, comprising 3 pairs of rectangles:

2 are 3x6 inches

2 are 3x12 inches and

2 are 6x12 inches.

Total material is therefore

2 * 3 * 6 + 2 * 3 * 12 + 2 * 6 * 12 sq in

= 36 + 72 + 144 sq in

= 252 sq in