Phil likes to collect baseball cards. He buys a pack of twenty each week for a year, but then loses half of them one day in a fire. How many baseball cards does Phil have left? Give me reasons, before answering the question
Since there are 20 cards in a pack and 52 weeks in a year, Phil starts by collecting 20 * 52 = 1040 baseball cards. He then loses half of them for 1040 / 2 = 520 cards remaining. So the final answer is 520.