Questions about the world of GMAT Math from other sources and general math related questions.
dddanny2006
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Combinatorics problem-Slot method

by dddanny2006 Fri Dec 27, 2013 10:56 am

Source-Veritas

How many Lunch combination meals(If you must choose exactly one of each :burger,side and drink) are possible at a fast food restaurant if you have 3 different burgers to choose from,three different drinks to choose from,and two different side to choose from?

The right answer is 18

This is my method of solving it-

3*3*2 ------------------Order doesn't matter,divide.
3!

Answer is 3.

Why am I wrong?We can have sides,drink,burger or burger,drink and sides.So order doesnt matter,but in the real answer they dont divide it by 3!.

Please explain.
RonPurewal
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Re: Combinatorics problem-Slot method

by RonPurewal Sat Dec 28, 2013 1:37 am

Hi,
As I mentioned here --
post94482.html#p94482
-- we can't continue to answer posts with titles that don't conform to the forum rules.

Please read the forum rules -- first thread in every folder -- and then re-post your question with an appropriate title (i.e., based on the first few words of the question).

Thanks.