A sociologist interested in youth culture is conducting a study on students' usage of Twitter. To determine how many times students log in to their accounts, she obtains a sample of 10 students. Students are asked how many times they log in to their account per month. The response are shown below.

Student Number Number of Uses

1 210

2 227

3 183

4 375

5 250

6 100

7 270

8 310

9 210

10 185

The correct answer = 240. What formula is used, and can you provide the formula steps.