Question 327354
There are four green blocks and four red blocks in a bag. 
a) What is the probability of selecting a red block, keeping it, then selecting
another red block?
P(red and red) = P(red)(P(red|red) = (4/8)(3/7) = 12/56 = 6/28
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b) What is the probability of selecting a green block, replacing it, then selecting a red block?
P(green and red) = P(green)*P(red) = (4/8)(4/8) = 1/4
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Cheers,
Stan H.