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Re: Combination [#permalink]
Why we multiplied 35 and 20. Till here I solved correctly but after that I added both these numbers.. Please explain me the last step.
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Re: Combination [#permalink]
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Reetika1990 wrote:
Why we multiplied 35 and 20. Till here I solved correctly but after that I added both these numbers.. Please explain me the last step.


It is a Fundamental Counting Principle .

Please review you math.

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Re: Combination [#permalink]
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For Reetika1990 or others who want an introduction, or refresher on, the Fundamental Counting Principle, this page might help: https://www.mathsisfun.com/data/basic-c ... ciple.html
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Combination [#permalink]
Three men (out of 7) and 3 women (out of 6) will be chosen to serve on a committee. In how many ways can the committee be formed?

Choosing 3 men out of 7, we require a combination of 3 out of 7 which is \( = \frac{7!}{(3! * (7 - 3)!)} = 35\)

Choosing 3 women out of 6, we require combination of 3 out of 6 which is \( = \frac{6!}{(3! * (6 - 3)!)} = 20\)

Now, we apply the fundamental counting principle which says that if there are n ways of doing something, and m ways of doing another thing after that, then there are \(n*m\) ways to perform both of these actions.

Therefore, there are \(35 * 20 = 700\) ways of forming the committee.
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