SOLUTION: A librarian chooses seven holiday books from a selection of ten to be displayed in the window of the library. In how many different ways can she choose the group of seven books?

Algebra ->  Permutations -> SOLUTION: A librarian chooses seven holiday books from a selection of ten to be displayed in the window of the library. In how many different ways can she choose the group of seven books?      Log On


   

Question 1104543: A librarian chooses seven holiday books from a selection of ten to be displayed in the window of the library. In how many different ways can she choose the group of seven books?
Answer by ikleyn(52776) About Me  (Show Source):
You can put this solution on YOUR website!
.
In C%5B10%5D%5E7 = 10%21%2F%287%21%2A3%21%29 = %2810%2A9%2A8%29%2F%281%2A2%2A3%29 = 120 ways.


C%5B10%5D%5E7 is the number of combinations of 10 items taken 7 at a time.

--------------
On Combinations,  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".


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.