probability

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out of 250 students interviewed at a community college, 90 were taking mathematics but not computer science, 160 were taking mathematics, and 50 were taking neither mathematics nor computer science. Find the probability that a student chosen at random was
a. taking just computer science
b. taking mathematics or computer science, but not both
c. taking computer science
d. not taking mathematics
e. taking mathematics, given that the student was taking computer science
f. taking computer science, given that the student was taking mathematics
g. taking mathematics, given that the student was taking computer science or mathematics
h. taking computer science, given that the student was not taking mathematics
i. not taking mathematics, given that the student was not taking computer science

• probability - ,

It would help if you proofread your questions before you posted them. You have not indicated that anybody is taking computer science or both.

• probability - ,

This is exactly how the question is written on the test. Does that mean it can't be answered since we don't have part of the problem?

• probability - ,

it's possible. You know 160 are taking math and OF the 160 90 are ONLY taking math leaving 70 taking both. 90+70(160) + 50 = 210. so 40 are taking c.s. but not math
90-math
70-math & c.s.
40-c.s.
50-neither
the rest is a:40/250, b:(90+40)/250, C:40/250, d:(50+40)/250

e gets tricky now is probability of students taking math out of the pool of (70+40)(the number taking c.s.) so 70/110
etc. etc.