How many three-digit whole numbers have at least one 7 or at least one 9 as digits?
<|im_start|>system
You are a helpful assistant.<|im_end|>
<|im_start|>user
How many three-digit whole numbers have at least one 7 or at least one 9 as digits?
Please reason step by step, and put your final answer within \boxed{{}}.<|im_end|>
<|im_start|>assistant

user
452
How many three-digit whole numbers have at least one 7 or at least one 9 as digits?
train