Higher November 2018 Paper 1 Q13
13 \(e : f = 2 : 3 \qquad \text{and} \qquad f : g = 5 : 4\)
Work out \(\quad e : g\)
Give your answer in its simplest form. [3 marks]
| Answer | Mark | Comments |
|---|---|---|
| Alternative method 1 | ||
| \(2 \times 5 : 3 \times 5\) or 10 : 15 and \(5 \times 3 : 4 \times 3\) or 15 : 12 | M1 | oe common value for \(f\) eg 10 : 15 : 12 or \(\dfrac{2}{3} : 1 : \dfrac{4}{5}\) |
| 10 : 12 | M1dep | oe unsimplified ratio condone fractions or decimals |
| 5 : 6 | A1 | |
| Alternative method 2 | ||
| \(3e = 2f\) and \(4f = 5g\) | M1 | oe equations |
| \(6e = 5g\) | M1dep | oe equation |
| 5 : 6 | A1 | |
Additional guidance
| Variables in an otherwise correct answer: the same variable scores 2 marks, eg \(5f : 6f\) different variables do not score, unless earlier marks can be awarded, eg \(5e : 6g\) with no working worth M1 or M1M1 | M1M1A0 M0M0A0 |