Higher January 2019 Paper 2 Q14
14 Marcus plays two games of tennis.
For each game, the probability that Marcus wins is 0.35
(a) Complete the probability tree diagram. (2)
(b) Work out the probability that Marcus wins at least one of the two games of tennis. (3)
| Scheme | Marks |
|---|---|
| 0.65 0.35, 0.65 0.35, 0.65 | B2oe |
| (2) |
Notes
B2oe: for all correct
If not B2 then award B1 for 0.65 in any of the 3 possible positions
NB all values may be given as fractions
| Scheme | Marks |
|---|---|
| \(0.35 \times 0.35\) or \(0.35 \times 0.65\) or \(0.65 \times 0.35\) or \(0.65 \times 0.65\) | M1 |
| \(0.35 \times 0.35 + 0.35 \times 0.65 + 0.65 \times 0.35\) or \(1 - 0.65 \times 0.65\) | M1 |
| 0.5775 | A1 |
| (3) | |
| (5 marks) |
Notes
M1: ft from (a)
M1: ft from (a)
A1: oe e.g. \(\dfrac{231}{400}\), 0.58 or 58% or better