SOLUTION: how do i compute and show my work for 9C3 and 9P3

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Question 1096086: how do i compute and show my work for 9C3 and 9P3
Answer by ikleyn(52787) About Me  (Show Source):
You can put this solution on YOUR website!
.
9C3 = C%5B9%5D%5E3 = 9%21%2F%283%21%2A%289-3%29%21%29 = 9%21%2F%283%21%2A6%21%29 = %289%2A8%2A7%29%2F%281%2A2%2A3%29 = 3*4*7 = 84.


It is the number of combinations of 9 items taken 3 at a time.




9P3 = 9*8*7 = 504.


It is the number of PLACEMENTS of 9 items taken 3 at a time.


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On Combinations, see the lessons
    - Introduction to Combinations
    - PROOF of the formula on the number of Combinations
    - Problems on 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".


Save the link to this textbook together with its description

Free of charge online textbook in ALGEBRA-II
https://www.algebra.com/algebra/homework/complex/ALGEBRA-II-YOUR-ONLINE-TEXTBOOK.lesson

into your archive and use when it is needed.