So far you have seen that 
can be used to determine the number of combinations. It is also possible to rewrite this formula without the permutation component.
So, the combination formula is as follows:
So far you have seen that can be used to determine the number of combinations. It is also possible to rewrite this formula without the permutation component.
So, the combination formula is as follows:
Read part a. of “Example 1” on pages 530 and 531 of the textbook to see how the combination formula is used when making selections.
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In how many ways can a coach choose his or her starting lineup of 5 basketball players if there are 15 players to choose from? Answer
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Have you ever had a combination lock given to you for a locker at school? Is this an appropriate name for this item? The word combination implies that order is not important. However, you know that if the numbers are not dialed in the right order with the correct rotation in between, the lock will not open. Perhaps these kinds of locks should be called permutation locks.