Daca 4 robinete umplu un bazin in 60 min, 6 robinete de aceelasi fel in cat timp umplu bazinul...

Răspuns :

4 robinete -------60 minute
6 robinete -------x minute
x = 4 × 60 : 6
x = 240 : 6
x = 40 minute
x=4x60 / 6
=240/6
=40