How many ways can Li Lei pay 49 yuan?
问李雷有多少种方法付49元？
A fellow Datong University graduate, Yuan Lei, threw the first wet blanket over the exuberance of Ms. Liu, Mr. Li and three friends not long after their July arrival in Beijing. Mr.
一位也是大同大学的毕业生，名叫袁磊（音译），他是第一个对七月份刚来北京不久的怀着美好憧憬的刘阳、李旭东和其他三个朋友泼冷水的。
Li Lei has two 20-yuan notes, three 10-yuan notes, two 5-yuan notes, three 2-yuan notes and three 1-yuan notes.
李雷有两张20元的钞票，三张10元的钞票，两张5元的钞票，三张2元的钞票和三张1元的钞票。
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