Foundation November 2021 Paper 2 Q19
19 The table gives information about the amounts of money, in euros, that 70 of Anjali’s friends spent last Saturday.
| Money spent (\(S\) euros) | Frequency |
|---|---|
| \(0 \lt S \leqslant 8\) | 6 |
| \(8 \lt S \leqslant 16\) | 14 |
| \(16 \lt S \leqslant 24\) | 19 |
| \(24 \lt S \leqslant 32\) | 25 |
| \(32 \lt S \leqslant 40\) | 6 |
One of Anjali’s 70 friends is going to be chosen at random.
(a) Find the probability that this friend spent more than 24 euros last Saturday. (1)
(b) Work out an estimate for the mean amount of money spent by Anjali’s friends last Saturday.
Give your answer correct to 2 decimal places. (4)
Give your answer correct to 2 decimal places. (4)
| Scheme | Marks |
|---|---|
| \(\dfrac{31}{70}\) | B1 |
| (1) |
Notes
B1: 31/70
Accept 0.44(28571…..) or 44.(2…)%
| Scheme | Marks |
|---|---|
| 4 × 6 + 12 × 14 + 20 × 19 + 28 × 25 + 36 × 6 (= 1488) or 24 + 168 + 380 + 700 + 216 (= 1488) | M2 |
\(\dfrac{4 \times 6 + 12 \times 14 + 20 \times 19 + 28 \times 25 + 36 \times 6}{70}\) oe eg ‘1488’ ÷ ‘70’ | M1 |
| Correct answer scores full marks (unless from obvious incorrect working) Answer: 21.26 | A1 |
| (4) | |
| (5 marks) |
Notes
M2: for at least 4 correct products added (need not be evaluated)
If not M2 then award:
M1 for consistent use of value within interval (including end points) for at least 4 products which must be added
or
correct midpoints used for at least 4 products and not added
M1: dep on at least M1
Allow division by their \(\Sigma f\) provided addition or total under column seen
A1: awrt 21.26
accept 21.3