your age will be three times his/her age
At some point during the lives of you and the youngest person, your age will be three times his/her age at that moment. Write an equation which models how old in years each of you will be when you are three times as old as the younger person. Explain the reasoning which helped you develop your equation. Solve the equation for your ages when you are three times as old as the youngest person. Are your answers reasonable?
The ages are 47, 30, 10.
I would like to also have reasoning behind the answers. I am here for help yes but I truly want to understand this for future knowledge.