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## #1 2009-03-25 13:43:14

simron
Real Member
Registered: 2006-10-07
Posts: 237

### Counting Problems

1. Say the license plates in Mathopolis consist of 2 letters followed by 3 digits. Assuming that none of the digits or letters can be the same, how many possible license plates are there?

Last edited by simron (2009-04-05 03:35:34)

Linux FTW

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## #2 2009-03-25 13:51:05

simron
Real Member
Registered: 2006-10-07
Posts: 237

### Re: Counting Problems

(Note that because I am turning these into Mathopolis questions, I will be posting these one by one.)

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## #3 2009-03-26 22:36:55

smiyc86
Member
Registered: 2009-03-19
Posts: 78

### Re: Counting Problems

26c2 * 10c3 * 5!

I love Maths and Music ... dunno which more

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## #4 2009-03-27 11:07:15

John E. Franklin
Member
Registered: 2005-08-29
Posts: 3,588

### Re: Counting Problems

or maybe 26 x 25 x 10 x 9 x 8 for license plate #1 problem.

igloo myrtilles fourmis

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## #5 2009-03-29 17:20:33

smiyc86
Member
Registered: 2009-03-19
Posts: 78

### Re: Counting Problems

well i think franklin is correct ... i didn't notice the "followed by" constraint ...

I love Maths and Music ... dunno which more

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## #6 2009-04-05 04:05:32

simron
Real Member
Registered: 2006-10-07
Posts: 237

I got

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## #7 2009-04-05 04:16:37

mathsyperson
Moderator
Registered: 2005-06-22
Posts: 4,900

### Re: Counting Problems

I get John's answer too. There are 10 digits to choose from.

Why did the vector cross the road?
It wanted to be normal.

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