SOLUTION: how many even 5 digit numbers are there?

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Question 933286: how many even 5 digit numbers are there?
Answer by tommyt3rd(5050) About Me  (Show Source):
You can put this solution on YOUR website!
clearly half of the 5 digit integers are even so 45000, but let's show it another way...
a%5Bn%5D=99998
a%5B1%5D=10000

using arithmetic sequences
n=%28a%5Bn%5D-a%5B1%5D%29%2Fd%2B1=89998%2F2%2B1=45000