SOLUTION: At a college, 55% of the students pass Math, 70% pass Biology, and 25% pass both of these courses. If a student is selected at random, Find the probability that a student passes Ma

Algebra ->  Probability-and-statistics -> SOLUTION: At a college, 55% of the students pass Math, 70% pass Biology, and 25% pass both of these courses. If a student is selected at random, Find the probability that a student passes Ma      Log On


   

Question 1115286: At a college, 55% of the students pass Math, 70% pass Biology, and 25% pass both of these courses. If a student is selected at random, Find the probability that a student passes Math given that he passed Biology.
Answer by ikleyn(52778) About Me  (Show Source):
You can put this solution on YOUR website!
.
In order for to make the situation maximally obvious/visible/tangible, imagine the equivalent formulation.



    There are 100 students; 55 of them passed Math; 70 passed Biology, and 25 passed both.

    Find the ratio of those who passed Math given that they passed Biology.



I do not need explain to you that this ratio is  25%2F70 - it is self-evidently.


Answer.  The probability under the question is  25%2F70 = 5%2F14 = 35.71%