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Homework Statement:
 A witness to a hitandrun accident tells the police that the license plate of the car in the accident, which contains three letters followed by three digits, starts with the letter A and contains both the digits 1 and 2. How many different license plates can fit this description?
Relevant Equations:

Counting
permutation(?) = P(n,r) = n!/(nr)!
I have a question and searched about at google and found an answer which I don't make sure. If there is 26 letters and 10 digits;
my answer is:
first letter: 1 way(which is A)
second letter: 26 way
third letter: 26 way
first digit: 1 way(which is 1)
second digit 1 way(which is 2)
third digit: 10 way
So, I think 26x26x10 license plates can fit this description.
But the other guy had said:
in addition above statements: order three digits ; P(3,3), order three letters ; P(3,3) , thus 26x26x10xP(3,3)xP(3,3)
Which one is correct? Would you please tell how we should think?
edit: I add a photo above so new arrivals can know the drill easily .
my answer is:
first letter: 1 way(which is A)
second letter: 26 way
third letter: 26 way
first digit: 1 way(which is 1)
second digit 1 way(which is 2)
third digit: 10 way
So, I think 26x26x10 license plates can fit this description.
But the other guy had said:
in addition above statements: order three digits ; P(3,3), order three letters ; P(3,3) , thus 26x26x10xP(3,3)xP(3,3)
Which one is correct? Would you please tell how we should think?
edit: I add a photo above so new arrivals can know the drill easily .
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