SOLUTION: Suppose that a certain college class contains 58 students. Of these, 25 are sophomores, 34 are history majors, and 11 are neither. A student is selected at random from the class.
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-> SOLUTION: Suppose that a certain college class contains 58 students. Of these, 25 are sophomores, 34 are history majors, and 11 are neither. A student is selected at random from the class.
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Question 633163: Suppose that a certain college class contains 58 students. Of these, 25 are sophomores, 34 are history majors, and 11 are neither. A student is selected at random from the class.
(a) What is the probability that the student is both a sophomore and a history major?
(b) Given that the student selected is a history major, what is the probability that she is also a sophomore?
Write your responses as fractions. Answer by ewatrrr(24785) (Show Source):
Hi,
58 students
25 are sophomores,
34 are history majors
11 are neither.
58-11 = 47
59 - 47 = 12
12, both soph and history majors
13 sophmores only
22 history majors only
P(soph & H maj) = 12/58 = 6/29
P(soph, given H maj) = = 12/22 = 6/11 |P(A|B) = P(A and B)/P(B)
