box of cereal measures 10 in .wide.12in . high, 3in deep .all surfaces made of cardboard and total overlapping cardboard in the box is 7in squared , how much cardboard is used to make a cereal box including the amount of overlapping parts ?

Answer 1

The area of all the exposed faces is

2(10*12 + 10*3 + 12*3) = 372 in^2
add to that the 7 in^2 of overlap.