SOLUTION: How many integers from 1 to 100 contain at least one 5 but do not contain a 7?

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Question 864652: How many integers from 1 to 100 contain at least one 5 but do not contain a 7?
Answer by richwmiller(17219) About Me  (Show Source):
You can put this solution on YOUR website!
There are 10 that begin with 5
There are 10 that end in 5
minus 55 so we don't count it twice
There are two that have both 5 and 7: 57 and 75
10+10-2-1=17