题目

Many people have low iron in their blood. But pregnant women need extra iron for their own health and their baby's health. Iron is important to the development of a baby's brain and central nervous system.In poor countries, however, providing all pregnant women with iron supplements can be a financial issue. Some experts say giving supplements to babies after they are born is enough.Someone who disagrees is Paul Christian, a nutritionist at the Johns Hopkins School of Public Health in Maryland. She and other scientists have been doing research in Nepal. She says their latest findings should se“五•五”端午节即将来临，某校准备组织七年级师生前往施秉县云台山旅游，计划租用豪华大巴汽车或中巴汽车来载运，已知一辆豪华大巴汽车装载人数是一辆中巴汽车装载人数的2倍还少10；若租用10辆豪华大巴汽车来载运就还差20人没有座位，而租用16辆中巴汽车来载运就刚好坐满．请问：①每辆大巴和中巴各装载多少人？此次旅游一共有多少人？②若租用一辆豪华大巴每天租金600元，租用一辆中巴每天租金450元；不准超载，此次旅游共3天应租用哪一种汽车最划算？租金一共多少元？