Respuesta :
Answer:
7
Step-by-step explanation:
if she got 30 from 6 cars then 30/6 is 5. $5 per car times 7 is $35
6*5=30 so she charges 5 dollars a car. so to earn 35 dollars she would have to wash an extra car here is the equation 30/6=5 anyway she needs to wash 7 cars because 7*5=35