what is meant by permutation

Question

anonymous · Answer

in short, selection, choosing

compassionate · Answer

WELCOME TO OPENSTUDY! Please see: https://www.khanacademy.org/math/probability/probability-and-combinatorics-topic/permutations_and_combinations/v/permutations It's basically changing the order of things. If I had 1, 2, 3. Then I changed it to 3, 2, 1. I could say that those numbers went through permutation.

anonymous · Answer

but if 3 would be repeated again then it is also pemutation ??

compassionate · Answer

Sorry, I have a headache. I got a nicotine overdose so I'm not feeling real good. 

"My fruit salad is a combination of apples, grapes and bananas" We don't care what order the fruits are in, they could also be "bananas, grapes and apples" or "grapes, apples and bananas", its the same fruit salad.
 	 
	"The combination to the safe was 472". Now we do care about the order. "724" would not work, nor would "247". It has to be exactly 4-7-2.
So, in Mathematics we use more precise language:

	If the order doesn't matter, it is a Combination.
	If the order does matter it is a Permutation.