Higher November 2017 Paper 1 Q20
20.
(a)
(i) How many different 5-digit whole numbers can be made using the digits 2, 3, 4, 5, and 6 when each digit can be used once only? [2]
(ii) What proportion of the 5-digit whole numbers are odd? [1]
(b) How many different 7-digit even whole numbers can be made using the digits 3, 4, 5, 6, 7, 8 and 9 when each digit can be used once only? [2]
| Scheme | Marks | Comments |
|---|---|---|
| (i) 120 | B2 | B1 for \(5 \times 4 \times 3 \times 2\ (\times 1)\) or \(5!\) or equivalent |
| (ii) \(\dfrac{2}{5}\) or equivalent | B1 |
| Scheme | Marks | Comments |
|---|---|---|
| 2160 | B2 | FT \(18 \times\) ‘their 120’ B1 for \(6 \times 5 \times 4 \times 3 \times 2 \times 3\) or \(\dfrac{3}{7} \times 7!\) or equivalent |
| (5) |