A box has 4 sides, two short sides which are width by height and two long sides which is length by height.
A) Surface area = 2(LxH) + 2(WxH)
Surface area = 2(10x4) +2(6x4)
Surface area = 2(40) +2(24)
Surface area = 80 + 48
Surface area = 128 square inches for each box.
128 square inches x 100 boxes = 12,800 square inches.
B) 1 can covers 14,000 square inches which is greater then the total of the 100 boxes, so she will need to buy 1 can of paint.
