To find the percentage difference between two numbers, we first need to find the absolute difference between them. In this case, the absolute difference between 180 and 72 is 108 (180 - 72 = 108).

Next, we need to find the average of the two numbers. The average of 180 and 72 is (180 + 72) / 2 = 126.

Now, we can calculate the percentage difference by dividing the absolute difference by the average and multiplying by 100. So, the percentage difference between 180 and 72 is (108 / 126) x 100 = 85.71%.

This means that 85.71% is the percentage by which 180 differs from 72. In other words, if we increase 72 by 85.71%, we will get 180.