Lu is making a quilt that is 20 squares wide and has 15 rows. The border of the quilt is made by using each toy design equally as often. Each square can only hold one design. How many of each design does she use for the border? What is the answer, please.

70

Step-by-step explanation:

We know that the border will be 20 squares twice, and

 15 squares twice also what is equivalent to the perimeter, because a quilt has 4 sides, with numbers, it would be the following:

20 * 2 + 15 * 2 = 40 + 30 = 70

So the border will have 70 squares in total. So if the border can have a single design, Lu can use any toy design 70 times if he wants the border to have the same toy design.