Answer:
49% probability that Mitchell will be a goalie today
Explanation:
If Coach White coaches, the probability of being goalie is 0.55.
Coach White has a 70% probability of coaching.
If Coach Jackson coaches, the probability of being goalie is 0.35.
Coach Jackson has a 100-70 = 30% probability of coaching.
What is the probability that Mitchell will be a goalie today?
This is 55% of 70% plus 35% of 30%
Then
P = 0.55*0.7 + 0.35*0.3 = 0.49
49% probability that Mitchell will be a goalie today