Answer
If Christina's age is = x
Aaron's age is = x + 6
Jeo's age = 3(x + 6 )
So, the sum of their ages can be write as,
[tex]x + x + 6 + 3(x + 6) \\ x + x + 6 + 3x + 18 \\ 5x + 24[/tex]
Also, they have given that the sum of their ages is 149
Therefore we can write a equation as,
[tex]5x + 24 = 149[/tex]
Now let's solve this and find the age of Christina
[tex]5x + 24 = 149 \\ 5x = 149 - 24 \\ 5x =12 5 \\ \frac{5x}{5} = \frac{125}{5} \\ x = 25[/tex]
Aaron's age is
[tex] x+ 6 \\ 25 + 6 \\ = 31[/tex]
Joe's age is
[tex]3(x + 6) \\ 3(25 + 6) \\ 3 \times 31 \\ = 93[/tex]
Hope this helps you.
Let me know if you have any other questions :-):-)