



 
Hi Gloria, If the number is greater than 10 and less than 20, then it must be 11,12,13,14,15,16,17,18,19. If you look carefully at these numbers you will notice all these numbers have the same number in the 10's spot. Therefore you now know the 10,s digit number. Now it should be very easy to calculate the 1's digit number. I hope this helps out. crnl  


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