The time of a class is (2/3) hours, which means that how much is regarded as the unit "1", divided into 3 parts on average, and there are 2 parts like this in the time of a class.
一节课的时间是(2/3)小时，表示把多少看作单位"1"，平均分成3份，一节课的时间有这样的2份．
<result>1</result>