<PRE><B>Question 516988</B>
In a business statistics class, there are 40 students and 24 of them are females. Suppose an experiment consists of selection two students at random with replacement. 
(i) construct a well-labelled tree diagram
(ii) What is the probability of selecting both females
# of ways to select 2 females: 24C2 = 276
# of ways to select pairs randomly: 40C2 = 780
P(select 2 females) = 276/780
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(iii) What is the probability of selecting at least one female student.
P(select 2 males) = 16C2/40C2
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So, P(at least one female) = 1 - P(2 males) = 1 - [16C2/40C2] = 0.8462
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Cheers,
Stan H.
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