Foundation June 2019 Paper 2R Q12
12 Ravina counts the number of matches in each of 40 boxes of matches.
The table shows information about her results.
| Number of matches | Frequency |
|---|---|
| 21 | 13 |
| 22 | 8 |
| 23 | 8 |
| 24 | 6 |
| 25 | 5 |
(a) Find the median of the numbers of matches in the boxes. (2)
(b) Work out the mean number of matches. (3)
| Scheme | Marks |
|---|---|
| \(\dfrac{13 + 8 + 8 + 6 + 5}{2}\) or \(\dfrac{(13 + 8 + 8 + 6 + 5) + 1}{2}\) or \(\dfrac{40}{2}\) or \(\dfrac{41}{2}\) or 20 or 20.5 | M1 |
| 22 | A1 |
| (2) |
Notes
M1: A clear attempt to list the 40 numbers in order and to find the middle number.
| Scheme | Marks |
|---|---|
| (21 × 13) + (22 × 8) + (23 × 8) + (24 × 6) + (25 × 5) (= 273 + 176 + 184 + 144 + 125) (= 902) | M1 |
| “902” ÷ 40 | M1 |
| 22.55 | A1 |
| (3) | |
| (5 marks) |
Notes
M1: At least 4 products correctly stated or evaluated
M1: dep
A1: Accept 22 or 23 if 22.55 seen