4MA0 Foundation June 2011 Paper 2 Q17
17 Here are two bags A and B.
Each bag contains 3 discs.
Each disc has a number on it.
Anton takes, at random, a disc from bag A and a disc from bag B.
His score is the sum of the numbers on these two discs.
(a) Complete the table to show all his possible scores.
(2)
| Bag A | ||||
|---|---|---|---|---|
| + | 1 | 3 | 5 | |
| Bag B | 2 | 5 | ||
| 4 | ||||
| 6 | ||||
(b) Find the probability that his score is 7 (2)
| Scheme | Marks | |||||||||
|---|---|---|---|---|---|---|---|---|---|---|
| B2 | |||||||||
| (2) |
Notes
B2: B2 fully correct 8 values
B1 for 1 row or 1 column correct
| Scheme | Marks |
|---|---|
| “3”/9 | M1 |
| 3/9 oe | A1 |
| (2) | |
| (Total 4 marks) |
Notes
M1: their number of 7’s and denominator of 9