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 53 and 70 is 17 (70 - 53 = 17).

Next, we need to find the average of the two numbers. The average of 53 and 70 is (53 + 70) / 2 = 61.5.

Now, we can calculate the percentage difference by dividing the absolute difference by the average and multiplying by 100. So, the percentage difference between 53 and 70 is (17 / 61.5) x 100 = 27.64%.

This means that the second number (70) is 27.64% higher than the first number (53). Alternatively, we could say that the first number (53) is 23.08% lower than the second number (70).