Question

A border to surround a picture is to be cut from an 10 1/2 in. by 10 1/2 in. mat board. If the picture is 7 3/4 in. by 7 3/4 in., what is width of the border? Enter an exact number as an in integer, fraction, or decimal.)

Answer 1

Let's make a diagram of the situation

Then we need to rest the side of the picture from the side of the mat board. This will tell us the total lenght availible to make the border. To this length, we need to divide it by 2, because the border has to be in both sides of the picture.

$10.5-7.75=2.75$

Divide by 2:

$\frac{2.75}{2}=1.375$

And since the mat and the picture are squared, the calculation for the vertical border is the same.

Thus the width of the border is 1.375 in, in all direction