Question

Pete is a very good student . The probability that he studies for his test and then passes it is 7/10 If the probability that Pete studies is 7/8 find the probability that Pete passes his test? given that he studied.

Answer 1

Answer:

The probability that Pete passes his test given that he studied = (8/10) = (4/5) = 0.80

Step-by-step explanation:

Let the event that Pete studies be S.

Let the event that Pete passes the test be P.

The probability that he studies for his test and then passes it is P(S n P) = 7/10

The probability that Pete studies is P(S) = 7/8

The probability that Pete passes his test given that he studied = P(P|S)

The conditional probability, P(A|B) is given mathematically as

P(A|B) = P(A n B) ÷ P(B)

So, the required probability, P(P|S) will be

P(P|S) = P(P n S) ÷ P(S)

P(P n S) = P(S n P) = (7/10)

P(S) = (7/8)

P(P|S) = P(P n S) ÷ P(S)

= (7/10) ÷ (7/8)

= (7/10) × (8/7)

= (8/10) = (4/5) = 0.80

The probability that Pete passes his test given that he studied = (8/10) = (4/5) = 0.80

Hope this Helps!!!