Question 313710
Among th 10 students of a class, three of them have blue eyes. If we pick randomly two students, what is the probability that 
A) both students will have blue eyes
# of ways to get 2 blue: 3C2 = 3
# of ways to get 2 randomly = 10C2 = 45
P(2 blue) = 3/45 = 1/15
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B) none of them will have blue eyes
# of ways to get no blue: 7C2 = 21
P(2 non-blue) = 21/45 = 7/15
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C) At least one of them will have blue eyes
= 1 - P(2 non-blue) 
= 1- 7/15
= 8/15
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Cheers,
Stan H.