View Full Version : prob.

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!

Powered by vBulletin™ Version 4.1.3 Copyright © 2016 vBulletin Solutions, Inc. All rights reserved.