How many three-digit whole numbers have at least one 7 or at least one 9 as digits?
A lot. You probably have to ask them yourself. But be careful of 667. He's pretty obsessive of his possessions.
There are 252 numbers between 100 and 999 with AT LEAST one 7 in them.
There are 252 numbers between 100 and 999 with AT LEAST one 9 in them.