Given the student is not a math major, what is the probability they asked for cream.

Question

There are 40 students, 10 math, 15 science, 15 art.

The probability a math student asks for cream is .7, the prob. a science student asks for cream is .3, and for art it is .1. Given the student is not a math major, what is the probability they asked for cream.

Answer 1

As student is not math major must be a science or art major. (30 students)

Science probability 15/30, asks for cream 3/10

Art probability 15/30 asks for cream 1/10

So probability of asking for cream is (15/30) x (3/10) + (15/30) x (1/10) = (15/30) x (3/10 + 1/10) = 2/10 = 0.2

Mike