Discrete Mathematics - Permutations/Combinations?

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Homework Help Overview

The problem involves calculating the number of different automobile license plates that can be issued, which consist of 2 letters followed by 3 digits, with the condition that neither letters nor digits can be repeated.

Discussion Character

  • Exploratory, Mathematical reasoning

Approaches and Questions Raised

  • Participants discuss the method of counting choices for letters and digits, with some suggesting multiplication of choices rather than addition. There is also a mention of factorials in the context of the problem.

Discussion Status

Some participants have provided calculations and results, while others are questioning the reasoning behind the addition versus multiplication of probabilities. There is an indication of differing interpretations regarding the approach to the problem.

Contextual Notes

Participants are exploring the rules of permutations and combinations, and there is a reference to available answer choices that may influence the discussion.

aliaze1
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Homework Statement



A certain state issues a series of automobile license plates such that each license plate
must have 2 letters followed by three digits. An example license plate would be AD 025 .
If the letters and the digits cannot be repeated, how many different license plates can be
issued by the state?

(a) 468,000 (b) 486,720 (c) 46,800 (d) 1,300 (e) 67,600

Homework Equations



Rules of factorials?
(ex: 5! = 5*4*3*2*1)

The Attempt at a Solution



How would I go about this?

I was thinking (26*25) + (10*9*8), but that is not an available option

Thanks
 
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well think of it like this: If the first 2 must be letters...how many choices do you have to pick the first letter?26 right...and if you pick one letter out then you have 25 remaining..so from the 25 you can pick one for the 2nd letter. and then for the rest of numbers it should be picking 3 numbers from 10..where the order is important
 
Why did you choose to add the probabilities? Try multiplying.
 
Integral said:
Why did you choose to add the probabilities? Try multiplying.

I originally thought they were separate things...

Thanks!
 
I got 468,000 by multiplying 26*25*10*9*8.
 
me2

bondgirl007 said:
I got 468,000 by multiplying 26*25*10*9*8.

thanks!
 

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