1. **State the problem:** Calculate the mean for the given frequency tables without using a calculator.
2. **Formula for mean of frequency distribution:**
$$\text{Mean} = \frac{\sum (x \times f)}{\sum f}$$
where $x$ is the value and $f$ is the frequency.
3. **First table (Age):**
Values: 5, 6, 7, 8
Frequencies: 2, 2, 5, 1
Total frequency $\sum f = 2 + 2 + 5 + 1 = 10$
Calculate $\sum (x \times f)$:
$$5 \times 2 = 10$$
$$6 \times 2 = 12$$
$$7 \times 5 = 35$$
$$8 \times 1 = 8$$
Sum:
$$10 + 12 + 35 + 8 = 65$$
Mean:
$$\frac{65}{10} = 6.5$$
4. **Second table (Number of phones):**
Values: 0, 1, 2, 3, 4, 5
Frequencies: 1, 3, 2, 0, 4, 0
Total frequency $\sum f = 1 + 3 + 2 + 0 + 4 + 0 = 10$
Calculate $\sum (x \times f)$:
$$0 \times 1 = 0$$
$$1 \times 3 = 3$$
$$2 \times 2 = 4$$
$$3 \times 0 = 0$$
$$4 \times 4 = 16$$
$$5 \times 0 = 0$$
Sum:
$$0 + 3 + 4 + 0 + 16 + 0 = 23$$
Mean:
$$\frac{23}{10} = 2.3$$
5. **Third table (Level):**
Values: 3, 4, 5, 6, 7
Frequencies: 1, 9, 7, 2, 1
Total frequency $\sum f = 1 + 9 + 7 + 2 + 1 = 20$
Calculate $\sum (x \times f)$:
$$3 \times 1 = 3$$
$$4 \times 9 = 36$$
$$5 \times 7 = 35$$
$$6 \times 2 = 12$$
$$7 \times 1 = 7$$
Sum:
$$3 + 36 + 35 + 12 + 7 = 93$$
Mean:
$$\frac{93}{20} = 4.65$$
**Final answers:**
- Mean age = 6.5
- Mean number of phones = 2.3
- Mean level = 4.65
Mean Frequency 2025B6
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