1995 AHSME Problems/Problem 20
Problem
If and are three (not necessarily different) numbers chosen randomly and with replacement from the set , the probability that is even is
Solution
The probability of being odd is , so the probability of being even is .
The probability of being odd is and being even is .
is even if and are both odd, with probability ; or and are both even, with probability . Thus the total probability is .
See also
1995 AHSME (Problems • Answer Key • Resources) | ||
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