Suppose that for students who are enrolled in college algebr

Suppose that, for students who are enrolled in college algebra, 79 percent are freshmen, 44 percent are female, and 31 percent are female and are freshmen. Your answers below should be entered as decimals and rounded to three decimal places.

(a) One student will be selected at random. What is the probability that the selected student will be a freshman or female (or both)?

(b) One student will be selected at random. What is the probability that the selected student will not be a freshman?

(c) Two students will be independently selected at random. What is the probability that both of the selected students will be female?

Solution

Let

Fr = freshmen
Fe = female

a)

P(Fr or Fe) = P(fr) + P(Fe) - P(Fr and Fe)

= 0.79 + 0.44 - 0.31

= 0.92 [ANSWER]

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b)

P(Fr\') = 1 - P(Fr) = 1 - 0.79 = 0.21 [ANSWER]

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c)

P(both Fe) = P(Fe)^2 = 0.44^2 = 0.1936 [ANSWER]