SOLUTION: There are 4 green blocks and 3 red blocks in a bag. What’s the probability of selecting three blocks of the same color randomly without replacement?

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Question 1162926: There are 4 green blocks and 3 red blocks in a bag. What’s the probability of selecting three blocks of the same color randomly without replacement?
Answer by Edwin McCravy(20054) About Me  (Show Source):
You can put this solution on YOUR website!
There is only 1 way to select three red blocks, which is to select them all.
There are 4 ways to select 3 green block, because when you select 3 green
blocks, you leave 1 green block behind, and there are 4 ways to leave 1
green block behind.

So there are 1+4 = 5 ways to selecting 3 blocks of the same color out of

[7 blocks CHOOSE 3] = 7C3 = 35 ways

So 5 successful ways out of 35 is a probability of 5/35 or 1/7.

Edwin