SOLUTION: In senior year of a high school graduating class of 100 students, 42 studied mathematics, 68 studied psychology, 54 studied history, 22 studied both mathematics and history, 25 stu

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Question 1146132: In senior year of a high school graduating class of 100 students, 42 studied mathematics, 68 studied psychology, 54 studied history, 22 studied both mathematics and history, 25 studied both mathematics and psychology, 7 studied history but neither mathematics nor psychology, 10 studied all three subjects, and 8 did not take any of the three. If a student is selected at random, find the probability that
(a) a student enrolled in psychology takes all three subjects.
(b) a student not taking psychology is taking both history and mathematics.
Answer by richwmiller(17219) About Me  (Show Source):
You can put this solution on YOUR website!
(a) a student enrolled in psychology takes all three subjects.
10/68= 5/34
(b) a student not taking psychology is taking both history and mathematics.
remove psych students and 8 who are not taking any of the three
100-68-8=24 are
or
5+12+7=24
12/24=1/2