Higher November 2017 Paper 1 Q6
6.
(a) The variables \(x\) and \(y\) are connected by the equation \(y = \dfrac{25}{x}\).
(i) Circle the correct statement. [1]
| \(x\) is inversely proportional to 25 | \(x\) is directly proportional to \(y\) |
| \(y\) is inversely proportional to \(x\) | \(y\) is directly proportional to \(x\) |
(ii) Find the value of \(x\) when \(y = 100\). [2]
(b) The distance-time graph shows the start of a journey.
Work out the speed of this part of the journey in metres per second. [2]

| Scheme | Marks | Comments |
|---|---|---|
| (i) \(y\) is inversely proportional to \(x\) indicated | B1 | |
| (ii) \((x =)\ 0.25\) or equivalent | B2 | B1 for \(100 = \dfrac{25}{x}\) seen Do not accept \(y = 0.25\) or equivalent |
| Scheme | Marks | Comments |
|---|---|---|
| \(\dfrac{4}{0.8}\) or equivalent | M1 | Allow e.g. ‘1 metre every 0.2 seconds.’ |
| 5 (m/s) | A1 | |
| (5) |