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 146 and 165 is 19 (165 - 146 = 19).

Next, we need to find the average of the two numbers. The average of 146 and 165 is (146 + 165) / 2 = 155.5.

Now, we can calculate the percentage difference by dividing the absolute difference by the average and multiplying by 100. So, the percentage difference between 146 and 165 is (19 / 155.5) x 100 = 12.21%.

Therefore, the percentage difference between 146 and 165 is 12.21%. This means that the second number (165) is 12.21% greater than the first number (146).