Find the mean of the following distribution:

| Class | 3-5 | 5-7 | 7-9 | 9-11 | 11-13 |
|---|---|---|---|---|---|
| Frequency | 5 | 10 | 10 | 7 | 8 |

Question

Find the mean of the following distribution:

| Class | 3-5 | 5-7 | 7-9 | 9-11 | 11-13 |
|---|---|---|---|---|---|
| Frequency | 5 | 10 | 10 | 7 | 8 |

Accepted Answer

Step 1: | Classes | $x_i$ | $f_i$ | $f_i x_i$ |
|---|---|---|---|
| 3-5 | 4 | 5 | 20 |
| 5-7 | 6 | 10 | 60 |
| 7-9 | 8 | 10 | 80 |
| 9-11 | 10 | 7 | 70 |
| 11-13 | 12 | 8 | 96 |
| **Total** | | **40** | **326** |
Step 2: Mean $= \frac{\sum f_i x_i}{\sum f_i} = \frac{326}{40} = 8.15$

Question

Solution