Discrete Mathematics - Permutations/Combinations?

AI Thread Summary
The discussion revolves around calculating the number of unique automobile license plates that can be formed with 2 letters followed by 3 digits, without repetition. Participants clarify that the correct approach involves multiplying the choices for letters and digits, rather than adding them. The correct calculation is 26 choices for the first letter, 25 for the second, and 10, 9, and 8 for the digits, leading to a total of 468,000 possible combinations. This method emphasizes the importance of understanding permutations in this context. Ultimately, the solution confirms that 468,000 is the correct answer.
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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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