



 
Byron, Since the number is odd there are 5 choices for the units digit, 1, 3, 5, 7 and 9. If you put a zero in the tens digit then there are 8 choices for the hundreds digit (not 0 and not the units digit) giving 8 x 1 x 5 possible combinations with a zero in the tens digit. If the tens digit is not zero then there are 8 choices for the tens digit and now only 7 choices for the hundreds digit giving 7 x 8 x 5 more possibilities. Thus the number of possible combinations is 8 x 1 x 5 + 7 x 8 x 5. Penny and Steve  


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