15 A darts team is going to play a match on Saturday and on Sunday. The probability that the team will win on Saturday is 0.45
If they win on Saturday, the probability that they will win on Sunday is 0.67 If they do not win on Saturday, the probability that they will win on Sunday is 0.35
(a) Complete the probability tree diagram.(2)
(b) Find the probability that the team will win exactly one of the two matches. (3)
Mark scheme (a)
Answer
Mark
Mark scheme
0.55, 0.67, 0.33, 0.35, 0.65
B1
for 0.55 in correct position
B1
for the branches for the second game correct
Additional guidance
Can be seen as fractions or percentages
Mark scheme (b)
Answer
Mark
Mark scheme
0.341
M1
for one correct product, eg \(0.45 \times \text{``}0.33\text{''}\) (=0.1485) or \(\text{``}0.55\text{''} \times \text{``}0.35\text{''}\) (=0.1925) or \(0.45 \times \text{``}0.67\text{''}\) (=0.3015) or \(\text{``}0.55\text{''} \times \text{``}0.65\text{''}\) (=0.3575)
