Intermediate November 2022 Unit 1 Q16
16. Express 1575 as a product of its prime factors in index form. [3]
| Scheme | Marks | Comments |
|---|---|---|
| For a correct method that produces 2 prime factors from the set {3, 3, 5, 5, 7} before the 2nd error. | M1 | Must be a method that involves only division. |
| 3, 3, 5, 5, 7 | A1 | CAO for sight of the five correct factors (Ignore 1s) |
| 32 × 52 × 7 | B1 | Do not FT non-primes. FT ‘their primes’ provided at least one index form used with at least a square. Allow (32)(52)(7) and 32.52.7 Do not allow 32,52,7. Inclusion of 1 as a factor gets B0. |