1. **State the problem:** We have a grouped frequency table of daily visitors to a gym with class intervals of width 10. We need to calculate the mean number of daily visitors.
2. **Formula for mean of grouped data:**
$$\text{Mean} = \frac{\sum f_i x_i}{\sum f_i}$$
where $f_i$ is the frequency of each class interval and $x_i$ is the midpoint of each class interval.
3. **Calculate midpoints $x_i$ for each class interval:**
- For 0–<10: $x_1 = \frac{0 + 9}{2} = 4.5$
- For 10–<20: $x_2 = \frac{10 + 19}{2} = 14.5$
- For 20–<30: $x_3 = \frac{20 + 29}{2} = 24.5$
- For 30–<40: $x_4 = \frac{30 + 39}{2} = 34.5$
- For 40–<50: $x_5 = \frac{40 + 49}{2} = 44.5$
- For 50–<60: $x_6 = \frac{50 + 59}{2} = 54.5$
- For 60–<70: $x_7 = \frac{60 + 69}{2} = 64.5$
4. **Given frequencies $f_i$:**
- $f_1 = 5$
- $f_2 = 7$
- $f_3 = 9$
- $f_4 = 8$
- $f_5 = 6$
- $f_6 = 3$
- $f_7 = 2$
5. **Calculate $f_i x_i$ for each class:**
- $5 \times 4.5 = 22.5$
- $7 \times 14.5 = 101.5$
- $9 \times 24.5 = 220.5$
- $8 \times 34.5 = 276$
- $6 \times 44.5 = 267$
- $3 \times 54.5 = 163.5$
- $2 \times 64.5 = 129$
6. **Sum frequencies and sum of $f_i x_i$:**
- $\sum f_i = 5 + 7 + 9 + 8 + 6 + 3 + 2 = 40$
- $\sum f_i x_i = 22.5 + 101.5 + 220.5 + 276 + 267 + 163.5 + 129 = 1180$
7. **Calculate mean:**
$$\text{Mean} = \frac{\sum f_i x_i}{\sum f_i} = \frac{1180}{40}$$
8. **Simplify fraction:**
$$\frac{\cancel{1180}}{\cancel{40}} = \frac{29.5}{1} = 29.5$$
9. **Interpretation:** The mean number of daily visitors to the gym is 29.5, meaning on average about 30 visitors come daily.
Mean Daily Visitors 3B9B16
Step-by-step solutions with LaTeX - clean, fast, and student-friendly.