Question 1146132
(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
*[illustration Seniors]