Foundation November 2020 Paper 1 Q19
19 Bags X and Y each contain counters.
| Bag X | Bag Y |
|---|---|
| 30 counters Each counter is green, white or yellow | 5 counters 3 green and 2 red |
(a) P(green counter from X) = P(red counter from Y)
Work out the number of green counters in X. [2 marks]
(b) All 35 counters are put into one bag.
One counter is picked at random.
Work out the probability that the counter is not red. [2 marks]
| Answer | Mark | Comments |
|---|---|---|
| \(\dfrac{2}{5}\) or \(\dfrac{30}{5}\) or \((30 \div 5 =)\) 6 or \(5 \times 6\) | M1 | oe fraction, decimal or percentage implied by \(2 \times \dfrac{30}{5}\) or \(2 \times 6\) |
| 12 | A1 | SC1 18 |
Additional guidance
| Accept a fully correct ratio build up method: eg 2 : 5, 4 : 10, 6 : 15, 8 : 20, 10 : 25, 12 : 30 with nothing on answer line eg 2 : 3, 4 : 6, 6 : 9, 8 : 12, 10 : 15, 12 : 18 with nothing on answer line | M1A0 M1A0 |
| \(30 \div 5 = 6\) and \(30 \div 3 = 10\) and \(30 \div 2 = 15\) (choice) | M0A0 |
| 6 must not come from \(2 \times 3\) |
| Answer | Mark | Comments |
|---|---|---|
| \(30 + 3\) or \(35 - 2\) or 33 or \((1 -)\ \dfrac{2}{35}\) | M1 | oe |
| \(\dfrac{33}{35}\) | A1 | oe fraction, decimal or percentage |
Additional guidance
| Ignore attempts to simplify or convert a correct fraction | |
| Ignore probability words | |
| Decimals or percentages to 2sf or better | |
| Condone 33 out of 35 or 33 in 35 with a correct fraction, decimal or percentage (together on answer line) but do not accept 33 : 35 with a correct fraction, decimal or percentage (together on answer line) | M1A1 M1A0 |