Respuesta :

s21251876

Answer:

35

This means he took 60 mins/5 to wash each car = 12 mins.

7 hours = 7* 60 mins= 420 mins

cars he washed in 7 hours = 420/12 = 35

OR

he took 3 hours to wash 15 cars so he can wash 30 in 6 hours, hs rate = 5 cars/ hour = 30 + 5 = 35