probability of 2 boys and 2 girls out of 6 children in total

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r_walid
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Topic: probability of 2 boys and 2 girls out of 6 children in total
PostTue Nov 03, 2009 8:13 pm Reply with quote
from a group of 3 B and 3G, what is the probability that if we were to pick 4 in total at random, that it would be 2 B and 2G?

1/10
4/9
1/2
3/5
2/3

please explain in detail your reasoning.
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venubab
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PostWed Nov 04, 2009 1:31 am Reply with quote
Answer 3/5

One of the arrangements BBGG
Probability=3/6 x 2/5 x 3/4 x 2/3=1/10

BBGG can be arranged in 4!/2!2! ways=6

Total no of way=6/10=3/5

or

Probability=3c2 x 3c2/6c4=3/5
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