Question 1121197
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Let x be the "ones" digit.


Then "tens" digit is (x+4) and "hundreds" digit is (((x+4)-7) = x-3.


Then the equation is


x + (x+4) + (x-3) = 16


3x +1 = 16  ====>  3x = 15  ====>  x= 5.


<U>Answer</U>.  The numbers is  295.
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<U>The lesson to learn from this solution</U> :


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    This problem is for one unknown and one equation.

    There is no any need to use three unknowns and three equations.
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