This might seem like an easy riddle for school kids at the first sight but don’t get yourself confused – it is a brain teaser for adults only and when you get to the solution you will be surprised what a nice puzzle it is.

Mom is 21 years older than her son.

In 6 years she will be 5 times older than her son.

Where is the father right now?


Don’t be confused, solve the equation and than practice some unit conversion.


If you count a bit you see that the son is -3/4 years old. This equals -9 months and that means that dad is in bed making love to mom right now...