SOLUTION: A math teacher gave a class two exams. There was 39% of the class who passed both exams and 50% of the class passed the first exam. What percent of those who passed the first exa

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Question 1076842: A math teacher gave a class two exams. There was 39% of the class who passed both exams and 50% of the class passed the first exam.
What percent of those who passed the first exam also passed the second exam?
Round your answer to three decimal places.
I think P(B and A)= .39 and P(A)=.5
I'm not sure though...

Answer by jorel1380(3719) About Me  (Show Source):
You can put this solution on YOUR website!
.5 passed the first exam, and .39 passed both. So:
.39/.5= amount who passed the 2nd exam=.78
.78* .5=.39 passed both exams. ☺☺☺☺