427,422 views
9 votes
9 votes
Gift Wrapping A gift box has the shape of a rectangular prism. Howmuch wrapping paper do you need to cover the box?4in13 in12in

Gift Wrapping A gift box has the shape of a rectangular prism. Howmuch wrapping paper-example-1
User Miroslav Trninic
by
2.5k points

1 Answer

17 votes
17 votes

The amount of wrapping paper you need is defined by the area of the prism's faces.

These are all rectangles so their area is equal to a*b where a is the length of the longest side and b that of the shortest.

We have two faces with sides 13in and 4in, two with sides 4in and 12in and two with sides 13in and 12in. Their areas are 13in*4in=52in^2, 12in*4in=48in^2 and 13in*12in=156in^2. Since we have two of each the total area is:

2*52in^2 + 2*48in^2 + 2*156in^2 = 512 in^2.

User JMcCarty
by
3.1k points