SOLUTION: In how many ways can a committee consisting of 2 faculty members and 5 students be formed if there are only 11 faculty members and 12 students eligible to serve on the committee?

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Question 1089768: In how many ways can a committee consisting of 2 faculty members and 5 students be formed if there are only 11 faculty members and 12 students eligible to serve on the committee?
Answer by ikleyn(52832) About Me  (Show Source):
You can put this solution on YOUR website!
.
Let us solve more simple problems first:

1.  In how many ways can you select 2 members among 11 faculty members?

    Since the order is not important, there are C%5B11%5D%5E2 = %2811%2A10%29%2F2 = 55 ways.


2.  In how many ways can you select 5 students among 12 students?

    Since the order is not important, there are C%5B12%5D%5E5 = %2812%2A11%2A10%2A9%2A8%29%2F%281%2A2%2A3%2A4%2A5%29 = 792 ways.


3.  Now, the selections among these two groups are independent.
    Hence, in all , you have 55*792 ways in your global problem.

These magic numbers  C%5Bn%5D%5Ek  are called the numbers of combinations of  n  things taken  k  at a time.

About combinations and about these numbers, see the lessons
    - Introduction to Combinations
    - PROOF of the formula on the number of Combinations
    - Problems on Combinations
    - OVERVIEW of lessons on Permutations and Combinations
in this site.

Also,  you have this free of charge online textbook in ALGEBRA-II in this site
    - ALGEBRA-II - YOUR ONLINE TEXTBOOK.

The referred lessons are the part of this online textbook under the topic  "Combinatorics: Combinations and permutations".


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