"A hat contains 2 red marbles, 3 blue marbles, and 4 green marbles. You choose two different marbles at random. What is the probability that they are the same color?"
red blue green
\(p=\frac{2}{9}\times \frac{1}{8}+\frac{3}{9}\times \frac{2}{8}+\frac{4}{9}\times \frac{3}{8}=\frac{5}{18}=0.278\)
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