Save the children riddle

[chelsea59]

If Peter is twice as old as Mark will be when Tom is as old as Peter is now, who is the oldest,next oldest and youngest?

[Dinkypuzzled]

Try Peter 24, Mark 6, Tom 18.

[quinie]

Well done,Dinkypuzzled. My head was going round in circles trying to work it out-did you use algebraic equations or just reason it out?

[nelios1]

also try Peter40,mark15,Tom35

[Dinkypuzzled]

Thanks quinie - I just tried jotting down a few numbers to try.