Answer:
0.4762
Step-by-step explanation:
There are 9C5 = 126 ways to choose 5 candidates to give speeches. There are (5C3)(4C2) = 60 ways that 3 of those candidates can be biology majors (and the other two can be non-biology majors). The probability of interest is ...
60/126 ≈ 0.4762
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nCk = n!/(k!(n-k)!)
i have no idea
1. 1350
2.2700
