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 361 and 423 is 62 (423 - 361 = 62).

Next, we need to find the average of the two numbers. The average of 361 and 423 is (361 + 423) / 2 = 392.

Now, we can calculate the percentage difference by dividing the absolute difference by the average and multiplying by 100. So, the percentage difference between 361 and 423 is (62 / 392) x 100 = 15.82%.

Therefore, the percentage difference between 361 and 423 is 15.82%. This means that the second number (423) is 15.82% greater than the first number (361).