Higher June 2022 Paper 1R Q1
1 Here is a biased spinner.
When the spinner is spun once, the probabilities that it lands on red or on yellow or on green are given in the table.
| Colour | red | yellow | purple | green |
|---|---|---|---|---|
| Probability | 0.25 | 0.2 | 0.2 |
(a) Work out the probability that the spinner lands on red or on yellow. (1)
Yang is going to spin the spinner 300 times.
(b) Work out an estimate for the number of times the spinner will land on purple. (3)
| Scheme | Marks |
|---|---|
| 0.45 | B1 |
| (1) |
Notes
B1: oe eg \(\dfrac{9}{20}, \dfrac{45}{100}\), 45%
| Scheme | Marks |
|---|---|
| eg 1 – (0.25 + 0.2 + 0.2) (= 0.35) or 1 – (“0.45” + 0.2) (= 0.35) or 300 × (0.25 + 0.2 + 0.2) (= 195) | M1 |
| eg 300 × “0.35” or 300 – “195” | M1 |
| 105 | A1 |
| (3) | |
| (4 marks) |
Notes
M1: allow use of their “0.45” from part (a), check the table
M1: for a complete method
A1: cao (award \(\dfrac{105}{300}\) M2 only)