Vanessa wants to buy a dress she saw at the mall, which costs $80, and she already has $20 in savings. Her parents give her $30 every week, but she also spends $10 each weekend at the arcades. How many weeks will she have to wait until she can gather enough money to buy the dress? Let's answer step by step:
Vanessa needs $80 $20 = $60 to buy the dress. She manages to gather $30 - $10 = $20 each week. The number of weeks she has to wait is 60 20 = 3 weeks. The answer: 3.