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 155 and 148 is 7.

Next, we need to find the average of the two numbers. The average of 155 and 148 is (155+148)/2 = 151.5.

Now, we can calculate the percentage difference by dividing the absolute difference by the average and multiplying by 100. So, the percentage difference between 155 and 148 is (7/151.5) x 100 = 4.62%.

Therefore, the percentage difference between 155 and 148 is 4.62%. This means that the difference between the two numbers is 4.62% of their average value.