The percentage difference between two numbers is a measure of how much one number differs from another in percentage terms. In this case, we are asked to find the percentage difference between 85 and 145.

To do this, we first need to find the absolute difference between the two numbers. The absolute difference is simply the positive difference between the two numbers, regardless of which one is larger. In this case, the absolute difference between 85 and 145 is:

|85 - 145| = |-60| = 60

Next, we need to find the average of the two numbers. The average is simply the sum of the two numbers divided by two. In this case, the average of 85 and 145 is:

(85 + 145) / 2 = 115

Now we can calculate the percentage difference between the two numbers. To do this, we divide the absolute difference by the average, and then multiply by 100 to get a percentage. In this case, the percentage difference between 85 and 145 is:

(60 / 115) x 100 = 52.17%

So the percentage difference between 85 and 145 is 52.17%. This means that 145 is 52.17% more than 85, or that 85 is 52.17% less than 145.