1MA0 Foundation November 2012 Paper 2 Q6
6 There are 3 counters in a bag.
One counter is red.
One counter is green.
One counter is blue.
Mike takes at random a counter from the bag.
He puts the counter back in the bag.
Then Ellie takes at random a counter from the bag.
(a) Is Ellie more likely to take a blue counter from the bag than Mike?
You must explain your answer. (1)
You must explain your answer. (1)
(b) Write a list of all the possible combinations of the two counters that Mike and Ellie can take. (2)
(c) Find the probability that Mike takes a blue counter and then Ellie takes a green counter. (1)
| Answer | Mark | Notes |
|---|---|---|
| No + reason | 1 | B1 for No because she has 1 choice out of 3 which is the same as Mike oe |
| Working | Answer | Mark | Notes |
|---|---|---|---|
| (r,g)(r,b)(g,b)(g,r)(b,g)(b,r) (r,r)(b,b)(g,g) | Complete list | 2 | M1 for listing pairs (at least 5 correct pairs) A1 for fully correct list (ignore repeats) |
| Answer | Mark | Notes |
|---|---|---|
| \(\dfrac{1}{9}\) | 1 | B1 for \(\frac{1}{9}\) oe (If M1A0 in (b), then SC B1 in (c) for \(\dfrac{\text{their number of (b,g)}}{\text{their total number of outcomes}}\)) |