Tickets for Changning Bamboo Sea Scenic Area are 100 yuan per person, and 20% off for groups (not less than 20 people). 17 students from Chongqing University traveled to Zhuhai, how to buy tickets more cost-effective?
长宁竹海风景区门票100元/人，团体(不低于20人)打八折．重庆大学17名学生到竹海旅游，怎样买票更合算？
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