Question 339817
based on how you defined the problem, there are 3 numbers to choose
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first number can be any digit so there are 10 choices
second number can be only 0 or 1 so there are 2 choices
third number can not include 0 if the second number is 0 or cannot include 1 if the second number is a 1, so there are 9 choices available 
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answer:  10*2*9=180