Respostas

2014-08-31T12:19:38-03:00
50   --- 20
600 --- x

x=12000/50
x=240/60
x=4horas
2 4 2
2014-08-31T12:21:54-03:00
50L   ----- 20min
600L -----  X

X = 600 . 20 / 50
X = 12 000 / 50
X = 240 min ou X = 4 horas :)
2 5 2