I NEED THE FIND THE TOTAL NUMBER OF COMBINATIONS FOR THE FOLLOWING NUMBERS IN LOTS OF 5
1,2,3,4,9,13,15,17,19,21,25,27,29,30,34,36
NANCY

Hi Nancy. Awhile ago, Kevin asked a similar question and Penny wrote back with a good explanation of how "Combinations" work.
Try using our search page at http://mathcentral.uregina.ca/QQ/QQsearch.html
You can type "number of four digit combinations" in the Title area to find the question and answer I'm looking at again. Or you can type in "combinations" in the keywords area to find many entries related to mathematical combinations.
The short answer to your question is to use the formula:
^{n!}/_{(k! x (nk)!)}
In your case, n is the number of valid numbers and k is the size of the "lots".
Hope this helps!
Stephen La Rocque>
