4MA0 Higher June 2015 Paper 3 Q18
18 \(y = \dfrac{2a}{b - c}\)
\(a = 42\) correct to 2 significant figures.
\(b = 24\) correct to 2 significant figures.
\(c = 14\) correct to 2 significant figures.
Work out the lower bound for the value of \(y\).
Give your answer correct to 2 significant figures.
Show your working clearly.
(3)
| Scheme | Marks |
|---|---|
| 41.5 or 42.5 or 24.5 or 23.5 or 14.5 or 13.5 | B1 |
| \((y =)\;\dfrac{2 \times 41.5}{24.5 - 13.5}\) | M1 |
| 7.5 | A1 |
| (3) |
Notes
A1: accept \(\dfrac{83}{11}\) or 7.55 or \(7.\dot{5}\dot{4}\) (depending on M1)
NB: Answer must come from correct working