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Random Integers Product Even

1350ApprenticeCombinatoricsNumber TheoryProbability

AMC 10A · 2007 · Problem 16

Integers $a, b, c,$ and $d$, not necessarily distinct, are chosen independently and at random from 0 to 2007, inclusive. What is the probability that $ad-bc$ is even?

Answer choices

A
\frac 38
B
\frac 7{16}
C
\frac 12
D
\frac 9{16}
E
\frac 58
0 students attempted0% solvedRating 1350

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