SOLUTION: how many of the numbers between 1000 and 3000 begin or end with 2?

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Question 919902: how many of the numbers between 1000 and 3000 begin or end with 2?
Answer by Edwin McCravy(20055) About Me  (Show Source):
You can put this solution on YOUR website!
Case 1:  The ones that begin with 2.
They are the three digit integers 000 through 999 with a 2 in 
front.  So there are 1000 of those. 

Case 2:  The rest.
Case 1 includes all the ones that begin and end in 2.  So we
don't want to count those again.  So the ones that end with 2 
but don't begin with 2 are the three digit numbers 100 through 
199 with a 2 placed on the end.  There are 100 of those.

Answer: 1000 + 100 = 1100  

Edwin