Question 383355
"The sum of the digits of a certain three digit number is nine. 
The sum of the hundreds and tens digits is equal to the ones digit minus one. The number, divided by nine, equals three times the ones digit. What is the number?" 
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h  +  t  + u   = 9
h  + t = u-1
(100h + 10t + u)/9 = 3u
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Rearrange:
h   +   t   +  u  =  9
h   +   t   -  u  = -1 
100h+ 10t   -26u  =  0
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Solve using any method you know to get:
h = 1 
t = 3
u = 5
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The number is 135
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Cheers,
Stan H.