Mary, who is sixteen years old, is four times as old as her brother?

Question

Mary, who is sixteen years old, is four times as old as her brother. How old will Mary be when she is twice as old as her brother?

DOESN'T MAKE SENSE!!!! IF SHE WAS EVER 4X THE AGE OF HER BROTHER SHE WILL ALWAYS BE 4X THE AGE!!!!! So if mary would be 24 when she is twice her brothers age he would be 12 but shouldn't she be 48?

Answer 1

 All you are expaining it  too coplicated.

Its  almost a trick question all you have to do is this 

Mary 16,17,18,19,20,21,22,23,24

Brother 4,5,6,7,8,9,10,11,12