买一桶油,付37.1元.这桶油连桶重8千克,用去一半油后连桶重4.5千克.每千克油多少元?

问题描述:

买一桶油,付37.1元.这桶油连桶重8千克,用去一半油后连桶重4.5千克.每千克油多少元?

37.1÷[(8-4.5)×2],
=37.1÷[3.5×2],
=37.1÷7,
=5.3(元).
答:每千克油5.3元.