SOLUTION: In a group of 30 students all study at least one of the subjects Physics and Biology. 20 attend the Physics class and 21 attend the Biology class. Find the probability that a stud

Question 812781: In a group of 30 students all study at least one of the subjects Physics and Biology. 20 attend the Physics
class and 21 attend the Biology class. Find the probability that a student chosen at random studies both
Physics and Biology.
Answer by ewatrrr(24785) (Show Source): You can put this solution on YOUR website!

 

Hi,



30 students 

20 attend the Physics class and 21 attend the Biology class. 

41 in class - 30 students = 11 (take both)  

P(both) = 11/30 

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