The average number of customers per day increased 25 percent during the sale. If the average number of customers per day before the sale was 120, what was the average number of customers per day during the sale?

The average number of customers per day during the sale was 150.

Step-by-step explanation:

This question can be solved using a rule of three.

Before the sale, the average number of customers per day was 120, which is 100% = 1.

Now, there are x customers, and since it is an increase of 25%, it is 100+25 = 125% = 1.25. So

120 - 1

x - 1.25

x = 1.25*120 = 150

The average number of customers per day during the sale was 150.