Question

Tyler is twice as old as his son. Ten years ago, Tyler was three times as old as his son. How old are they now?

Answer 1

In these types of problems it is best to assign a symbol for each unknown so that you can then formulate an equation.
In this example, lets call Tylers age now 't' and his son's age now 's'. We can then write:\[t=2s\]which states Tyler is twice as old as his son.
Now, ten years ago, Tyler would be \(t-10\) years old and his son would be \(s-10\) years old. So we can write the second condition as:\[t-10=3(s-10)\]which states Tyler was three times as old as his son ten years ago.
Now, just substitute \(t=2s\) from the first equation into the second and solve to find 's'. Then use the first equation again to find 't' as you now know 's'.