Thread: conditional probability hel

hi everyone. How do i identify questions about conditional probability? Like i have this question, In a senior year of high school graduating class of 100 students, 42 studied maths, 68 psycology, 54 history, 22 studied both history and math, 25 studied both maths and psycology, 7 studied history only, 10 studied all, and 8 did not study neither of the subjects. If a student is selected at random, find the probability that
a) a person enrolled in psycology takes all 3 subjects
b) a person not taking psycology is taking both history and maths.

i am not asking for the solution to this problem just want to know how i can identify it as a conditional probability question. I know it is so because it's in the section of conditional probability in my book . I have previously done similar questions which are not of conditional probability so how do i differentiate between the two because this question is not giving the correct answer unless it is solved by formula for conditional probability.