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Possible Combinations

Date: 4/17/96 at 17:41:0
From: Anonymous
Subject: Probability

My teacher looked in his desk.  He found a master lock.  On the
lock there were 4 sections that held 10 numbers, 0 - 9.  He asked
us to tell him how many different combinations were possible.

I have two different ideas.  I thought I could multiply
10 X 8 X 7 ... X 1.  I'm not sure why I thought this, other than 
that I have seen problems worked like this.  

I tried a few examples.  If there were only 2 sections and 2 
numbers, I would get 4 possibilities.  Then I began to think it 
may be worked 10 X 10 x 10 x 10.  I thought about this clue 
when I worked 2 X 2.

Am I on the right track?  If so, which one?

Date: 4/17/96 at 19:39:54
From: Doctor Jodi
Subject: Re: Probability

Yes, I think you've got a couple of good ideas here...

The number of possibilities is going to be determined by the
number of choices for first times the number of choices for second 
times the number of choices for third...  and so on.

Does this make sense?

So how many possibilities do you find?

-Doctor Jodi,  The Math Forum

Associated Topics:
High School Permutations and Combinations

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