We are given that the sum of two numbers is 24. If "x" and "y" are the two numbers then we have that:
[tex]x+y=24[/tex]We are also given that one number is three times the other, this is expressed as:
[tex]x=3y[/tex]Now, we substitute the value of "x" from the second equation in the first equation:
[tex]3y+y=24[/tex]Now, we add like terms:
[tex]4y=24[/tex]Now, we divide both sides by 4:
[tex]y=\frac{24}{4}=6[/tex]Therefore, the first number is 6. Now, we substitute the value of "y" in the second equation:
[tex]\begin{gathered} x=3(6) \\ x=18 \end{gathered}[/tex]Therefore, the other number is 18.