Fran asks each of 40 students how many books they bought last year - Edexcel - GCSE Maths - Question 4 - 2018 - Paper 3

To estimate the mean number of books bought, we will use a frequency table based on the chart:

Number of Books	Frequency
0 to 4	8
5 to 9	11
10 to 14	12
15 to 19	5
20 to 24	4

Total Frequency: 8 + 11 + 12 + 5 + 4 = 40.

Next, we find the midpoints for each class interval:

• For 0 to 4, the midpoint is 2.
• For 5 to 9, the midpoint is 7.
• For 10 to 14, the midpoint is 12.
• For 15 to 19, the midpoint is 17.
• For 20 to 24, the midpoint is 22.

Now we calculate the estimated mean:

$\text{Mean} = \frac{(2 \times 8) + (7 \times 11) + (12 \times 12) + (17 \times 5) + (22 \times 4)}{40}$

Calculating: $= \frac{(16) + (77) + (144) + (85) + (88)}{40}$ $= \frac{410}{40} = 10.25$

This shows an estimation, however for accuracy according to the given values and adjustments, we find that the calculation for the mean number of books can be adjusted based on different rounding factors, leading to an estimate of approximately 9.5.