Foundation November 2018 Paper 1 Q25
25 Marcin buys 7 rulers and 15 crayons for £7.
A ruler costs 12p more than a crayon.
Find the cost of one crayon. [5]
| Answer | Marks | Part marks and guidance | |
|---|---|---|---|
| 28 or [£][0].28 | 5 | B1 for \(7r + 15c = 7[00]\) or [\(r =\)] \(c + [0.]12\) M1 for \(7(c + [0.]12) + 15c = 7[00]\) or better oe or \(r - c = [0.]12\) M1 for \(7c + 84 + 15c = 7[00]\) or better oe or \(7r - 7c = [0.]84\) M1 for \(15c + 7c = 7[00] - [0.]84\) or better | Allow any pair of letters, Trial-and-improvement will score 0 or 5 only allow work in pence or pounds i.e. removing brackets i.e. rearranging their equation |