If one number is thrice the other and their sum is $16$, find the numbers If one number is thrice the other and their sum is $16$, find the numbers. I tried, Let the first number be $x$ and the second number be $y$ Acc. to question $$ \begin{align} x&=3y &\iff x-3y=0 &&(1)\\\ x&=16-3y&&&(2) \end{align} $$

The problem statement says $$x+3x=16,$$ hence $$x=4,\\\3x=12.$$