4400 Higher November 2010 Paper 3 Q18
18 Make \(x\) the subject of \(P = \dfrac{100(y - x)}{x}\)
(4)
| Scheme | Marks |
|---|---|
| \(xP = 100(y - x)\) or \(P = \dfrac{100y - 100x}{x}\) | M1 |
| \(xP = 100y - 100x\) | M1 |
| \(x(P + 100) = 100y\) | M1 |
| \(\dfrac{100y}{P + 100}\) oe | A1 |
| (4) | |
| (4 marks) |
Notes
M1: \(P = 100y/x - 100x/x\)
M1: \(P + 100 = 100y/x\)
M1: \(x(P + 100) = 100y\)