Validate input has up to 2 decimal places

I need to validate hours put into a textbox.  I want to allow hours to be from 0-24 and allow up to 2 decimal places. so it has to accept


0
0.00
1.5
2.25
but not 2.225 or 25
I put a range validator that check that the value is from 0-24 but it doesn't check that there are 2 decimal places or less.  how do I do that?

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