ANSWER
7 sales
EXPLANATION
We are given that over 5 days, the number of sales made are:
8, 7, 9, 5 and 7
To find the average sales made per day, we have to add up all the sales made over the 5 days and then divide by the number of days (5):
[tex]\begin{gathered} \text{Average Sales = }\frac{Sum\text{ of all sales}}{number\text{ of days}} \\ \text{Average Sales = }\frac{8\text{ + 7 + 9 + 5 + 7}}{5}\text{ = }\frac{36}{5} \\ \text{Average Sales = 7.2 }\cong7\text{ sales} \end{gathered}[/tex]An average of 7 sales were made per day.