1MA0 Higher November 2013 Paper 2 Q3
3 Bill has some counters in a bag.
3 of the counters are red.
7 of the counters are blue.
The rest of the counters are yellow.
Bill takes at random a counter from the bag.
The probability that he takes a yellow counter is \(\dfrac{2}{7}\)
How many yellow counters are in the bag before Bill takes a counter? (2)
| Answer | Mark | Notes |
|---|---|---|
| 4 | 2 | M1 for 14 or \(\dfrac{3 + 7}{n} = \dfrac{5}{7}\) or any fraction equivalent to \(\dfrac{2}{7}\) or \(\dfrac{5}{7}\) A1 cao |