Respostas

2014-03-03T04:14:38-03:00
Primeiro encontra o tempo total

tempo total = 10 min + 30 min = 40 min

40 min =  \frac{40}{60}  =  \frac{2}{3} h


Vm =  \frac{distancia}{tempo}

Vm =  \frac{50 km}{1} /  \frac{2}{3 } h

Vm =  \frac{50}{1}  .  \frac{3}{2}  = 75 km/h