SOLUTION: Hi A manufacturer wanted to make 2 colour hand phones. He was given a choice of 10 colours. How many combinations could he make. Thanks

Question 1198736: Hi
A manufacturer wanted to make 2 colour hand phones. He was given a choice of 10 colours. How many combinations could he make.
Thanks
Answer by ikleyn(52879) (Show Source): You can put this solution on YOUR website!
.


It is   =  = 45,  the number of combinations of 10 items (colors) taken 2 at a time.


The order of items (of colors) does not matter in this problem,
so we use combinations.

Solved.

----------------

On Combinations, see introductory 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.

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