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challenge 1-B homework question

 
 
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challenge 1-B homework question
by Hannah Guan - Saturday, 7 January 2017, 10:54 AM
 

For challenge 1-B (counting and probability), home work 3, questions F6 and F7, does the notation (4, 1) denote Permutation or Combination?


Thanks.

Hannah

 
Picture of John Lensmire
Re: challenge 1-B homework question
by John Lensmire - Monday, 9 January 2017, 9:57 AM
 

Recall that the notation $\displaystyle \binom{n}{k}$ (which you read as "n choose k") is for combinations. The formula is $$\binom{n}{k} = \frac{n!}{k!\times (n-k)!}.$$ Combinations are used for choosing objects without order. (Permutations are when there is order.)


Best,
John