Higher June 2023 Paper 2 Q2
2 A biased spinner can land on green or on yellow or on brown or on pink.
The table gives the probabilities that, when the spinner is spun, it will land on green or on yellow or on brown.
| Colour | green | yellow | brown | pink |
|---|---|---|---|---|
| Probability | 0.32 | 0.13 | 0.28 |
Timucin spins the spinner 200 times.
Work out an estimate for the number of times the spinner lands on pink.
(3)
| Scheme | Marks |
|---|---|
| 1 – (0.32 + 0.13 + 0.28) oe eg 1 – 0.73 (= 0.27) or 0.32 × 200 (= 64) or 0.13 × 200 (= 26) or 0.28 × 200 (= 56) or 0.73 × 200 (= 146) | M1 |
| [1 – “0.73”] × 200 oe eg “0.27” × 200 or 200 – “64” – “26” – “56” or 200 – “146” | M1 |
| Correct answer scores full marks (unless from obvious incorrect working) Answer: 54 | A1 |
| (3) | |
| (3 marks) |
Notes
M1: (0.27 may be seen in table)
[could work with percentages eg 100 – 32 – 13 – 28 (=27)]
M1: for a complete method or for an answer of \(\dfrac{54}{200}\)