Higher November 2018 Paper 5 Q3
3 Geoff has two fair spinners.
He spins both spinners and multiplies the numbers on each spinner.
(a) Complete the table.
| Spinner A | ||||
|---|---|---|---|---|
| × | 1 | 7 | 9 | |
| Spinner B | 2 | 2 | 14 | 18 |
| 3 | 3 | 21 | 27 | |
| 4 | 4 | 28 | ||
| 5 | 5 | 35 | ||
[1]
(b) Geoff wants to work out the probability that the outcome of the multiplication is an even number or a prime number.
Here is his working.
Here is his working.
The probability the outcome is an even number is \(\frac{6}{12}\).
The probability the outcome is a prime number is \(\frac{3}{12}\).
The probability the outcome is an even number or a prime number is \(\frac{6}{12} + \frac{3}{12} = \frac{9}{12}\).
Geoff is wrong.
Explain his error and give the correct answer. [2]
| Answer | Marks | Part marks and guidance | |
|---|---|---|---|
| 36 and 45 | 1 | ||
| Answer | Marks | Part marks and guidance | |
|---|---|---|---|
| Even and prime are not mutually exclusive oe | 1 | e.g. 2 is both prime and even 2 is counted twice One number is prime and even Do not accept there are only 2 prime numbers | |
| \(\dfrac{8}{12}\) oe | 1 | ||