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Probability - boys & girls

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by GmatMathPro » Fri Dec 30, 2011 6:08 pm
karthikpandian19 wrote:From a group of 3 boys and 3 girls, 4 children are to be randomly selected. What is the probability that equal numbers of boys and girls will be selected?

A. 1/ 10
B. 4/9
C. 1/2
D. 3/5
E. 2/3
If there is an equal number of boys and girls in the group of 4, then there are 2 boys and 2 girls. There are 3C2=3 ways to select the two boys, and 3C2=3 ways to select the two girls. So, there are 3*3=9 ways to choose 2 boys and 2 girls.

There are 6C4 total=15 total groups of 4, so the probability in questions is 9/15 or 3/5

Ans: D
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by karthikpandian19 » Sat Dec 31, 2011 12:38 am
OA is D
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