Higher November 2019 Paper 4 Q6
6 A bag of sweets contains only mints, sherberts and toffees.
The ratio of the number of mints to sherberts is 2 : 3.
The ratio of the number of sherberts to toffees is 7 : 5.
What fraction of the sweets are sherberts? [3]
| Answer | Marks | Part marks and guidance | |
|---|---|---|---|
| \(\frac{21}{50}\) | 3 | M1 for two ratios with a common number of sherberts e.g. 14 : 21 or 21 : 15 or 50 and M1 for \(\frac{\textit{their}\ 21}{\textit{their}\ (14 + 21 + 15)}\) only after valid attempt to create a triple ratio eg 0 for \(\frac{3 + 7}{2 + 3 + 7 + 5}\) etc allow any correct method | Alternative : M1 for 7 ÷ 3 implied by 2.3[3…] oe or better and M1 for 5 ÷ 2.3[3…] oe implied by 2.1428…… (exact = \(\frac{15}{7}\)) or 2 × 2.3[3..] oe and e.g. 2 : 3 : their \(\frac{15}{7}\) (= 14 : 21 : 15) or their \(\frac{14}{3}\) : 7 : 5 |