Question

Homework are approaching and Helen is allocating time to studying for Homeworks. She plays for the very successful women’s lacrosse team and must schedule her studying around lacrosse practices and play-off games. The entire team assumes that the probability of making the play-offs is 70%. Helen thinks that with the appropriate preparation, she has a 60% chance of getting an A in Marketing, but this chance decreases to 55% if the lacrosse team makes the play-offs. what is the probability that Helen either gets an A in marketing or the team makes the play offs?

Answer 1

Let the event of the team making it to playoffs be given by S

Let the event of Helen getting an A be given by A

We are provided the following information:

P(S) = 0.70

P(A) = 0.60

P(S and A) = 0.55

We need to find P(S or A)

Using the additive theorem of probability we get:

P(S or A) = P(S) + P(A) - P(S and A)

= 0.70 + 0.60 - 0.55

= 0.75

Hence  the probability that Helen either gets an A in marketing or the team makes the play offs is 75% or 0.75.

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