There are five members of the Math Club. In how many ways can the positions of officers, a president, and a treasurer, be chosen? I thinked it's just 5 factorial. But the answer is 20. Which means they divided by 3 factorial... Why ?(Crying)

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- Sep 14th 2012, 07:35 AMShwemsPermutations and combinations
There are five members of the Math Club. In how many ways can the positions of officers, a president, and a treasurer, be chosen? I thinked it's just 5 factorial. But the answer is 20. Which means they divided by 3 factorial... Why ?(Crying)

- Sep 14th 2012, 07:49 AMkalyanramRe: Permutations and combinations
You have two offices (President, Treasurer). Now you have to choose 2 people from a group of 5 how many ways can this can be done.

__Spoiler__: - Sep 14th 2012, 08:10 AMemakarovRe: Permutations and combinations
See k-permutations.