It takes 20, 12, and 15 days for A, B, and C to process a batch of parts. Now, A, B, and C are cooperating in this project, so how many hours will it take to complete the task?
加工一批零件，甲乙丙三人独做所需时间分别为20、12、15天，现在这项工程由甲乙丙合作，那么几小时才能完成任务？
<result>120</result>