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yohy20
07-27-2010, 11:00 PM
how many different 10-letter words (real or imaginary) can be formed from the letters in the word MONOCHROME?

okay, so I did this by doing permutation and my solution is 10!/2!2! and came up with an answer 907,200.. I'm just checking if my answer's correct.
thank you in advance.

Dragan
07-27-2010, 11:15 PM
how many different 10-letter words (real or imaginary) can be formed from the letters in the word MONOCHROME?

okay, so I did this by doing permutation and my solution is 10!/2!2! and came up with an answer 907,200.. I'm just checking if my answer's correct.
thank you in advance.


The letter O appears 3 times (not 2 times).

yohy20
07-27-2010, 11:20 PM
okay, so the solution is 10!/3!3! then? and the answer is 100,800
thanks so much!

Dragan
07-27-2010, 11:26 PM
okay, so the solution is 10!/3!3! then? and the answer is 100,800
thanks so much!

Well, the letter M appears 2 times (not 3 times) - so now what are going to do?:)

yohy20
07-27-2010, 11:33 PM
oh yeah, so its 10!/3!2!?

Dragan
07-27-2010, 11:48 PM
oh yeah, so its 10!/3!2!?

Yes, and as a check you should be careful and note that the integers in the denominator should add up to the integer value in the numerator. That is,

10!/ (2!3!1!1!1!1!1!) = 10!/ (2!3!)

because the other letters (not previously mentioned) appear only 1 time.

yohy20
07-28-2010, 12:02 AM
right, thanks for helping me out!