say you have to find how many 4 letter combination's there are of the word "outlook"
how do you do that?
If it where a word with no repeated letters it wouldnt be bad ie 7C4 (Pretty sure) = 7!/(4!3!) = 35
but what is this, maybe it's 6c4 = 6!/(2!2!) = 180? I know that is wrong the answer is 15.
Thanks.
I made a mistake it should have been 6!/2!4! = 15
but when I do it like that for the others it doesnt work, and it wouldnt work if there where two different letters that where repeated.
osborne
7 letter's
so
7!/ (4!(7-4)!) = 35 {thats with no repeated letters} right answer is 25
?