1MA0 Higher June 2012 Paper 1 Q24
24 Express the recurring decimal \(0.2\dot{8}\dot{1}\) as a fraction in its simplest form. (3)
| Working | Answer | Mark | Notes |
|---|---|---|---|
| eg. \(x = 0.28181...\) \(100x = 28.181...\) \(99x = 27.9\) | \(\dfrac{31}{110}\) | 3 | M1 for 0.28181(...) or 0.2 + 0.08181(...) or evidence of correct recurring decimal eg. 281.81(...) M1 for two correct recurring decimals that, when subtracted, would result in a terminating decimal, and attempting the subtraction eg. \(100x = 28.1818\ldots\), \(x = 0.28181\ldots\) and subtracting eg. \(1000x = 281.8181\ldots\), \(10x = 2.8181\ldots\) and subtracting OR \(\dfrac{27.9}{99}\) or \(\dfrac{279}{990}\) oe A1 cao |