5 people were asked about the time in a week they spend in doing social work in their community. They said 10, 7, 13, 20 and 15 hours, respectively. Find the mean (or average) time in a week devoted by them for social work.

Explanation

To find the mean (or average) time spent by the five people on social work, we can follow these steps:

### Step 1: List the hours spent by each person
The hours spent by the five people are:
- Person 1: 10 hours
- Person 2: 7 hours
- Person 3: 13 hours
- Person 4: 20 hours
...