Foundation November 2019 Paper 1 Q15
15 \(ADB\) and \(CD\) are straight lines.

Not drawn accurately
angle \(ADC = 5 \times\) angle \(CDB\)
Work out the size of angle \(ADC\). [3 marks]
| Answer | Mark | Comments |
|---|---|---|
| Alternative method 1 | ||
| 5 : 1 or 1 : 5 or \(\dfrac{5}{6}\) or \(\dfrac{1}{6}\) or 6 (parts) | M1 | may be implied by second mark may be seen on diagram |
| \(180 \div 6\) or 30 | M1dep | |
| 150 | A1 | |
| Alternative method 2 | ||
| \(5x + x = 180\) or \(6x = 180\) | M1 | any letter may be implied by second mark |
| \(180 \div 6\) or 30 | M1dep | |
| 150 | A1 | |
Additional guidance
| If Trial and Improvement used, 30 seen is M2 but 150 must be chosen as the answer for M2A1 | |
| \(360 \div 6\) | M1M0A0 |