Question. Jim buys a package of 20 car washes. Since He bought a package he only has to pay 60%. A carwash normally costs 15 dollars. How much did he pay for the package?
Answer. 180
What step-by-step reasoning justifies that answer?
Reasoning: He had to pay for 20 * .6 = 12 car washes. That means he had to pay 12 * 15 = $180.