To find the percentage difference between two numbers, we first need to calculate the absolute difference between them. In this case, the absolute difference between 180 and 200 is 20.

Next, we need to find the average of the two numbers, which is (180 + 200) / 2 = 190.

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 200 is:

| (180 - 200) / 190 | * 100 = 10.53%

Therefore, the percentage difference between 180 and 200 is 10.53%. This means that 200 is 10.53% greater than 180.