To raise funds for uniforms and travel expenses, the soccer team is holding a car wash in a part of town with a lot of car and truck traffic. The team spent $90 on supplies like sponges and soap. They plan to charge $10 per car and $20 per truck. Their goal is to raise $460.
How many cars do they have to wash if they washed the following numbers of trucks?'
4 trucks
Do not include units cars in your answer