SOLUTION: There are 8 blue, 3 green, and 10 yellow socks in a drawer. You randomly choose one, then another, without replacement. Find the probability of choosing two blue socks

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Question 442929: There are 8 blue, 3 green, and 10 yellow socks in a drawer. You randomly choose one, then another, without replacement. Find the probability of choosing two blue socks
Answer by swincher4391(1107) (Show Source):
You can put this solution on YOUR website!
Let's count how many socks we have all together:
8 + 3 + 10 = 21.
We have socks.
Now how many blue socks do we have?

So we have a chance of drawing a blue sock.
We take a blue sock and we don't replace it.
How many socks do we have left? 20. How many blue socks do we have left? 7.
We have a 7/20 chance of drawing a blue sock.
So what is P(Blue Sock and Another Blue Sock) = P(Blue Sock) * P(Another Blue Sock) = (8/21) * (7/20)
Let's simplify this:
To make this easier, let's take each term into it's prime decomposition. This is if you have trouble simplifying fractions.

If you aren't comfortable with that, then just multiply it straight out