不同问题求平均值的算式类型是不同的,如果不能根据问题所决定的数量关系把这些式子类型区别开来,则解答容易出错. 问题1 某地气象站测得某天四个时刻的气温分别为:早7点是零下2.5℃;中午12点是零上5.3℃;晚上7点是零下1℃;凌晨2点是零 Different types of equations for calculating the average value of different problems are different. If you cannot distinguish these types of subtypes based on the quantitative relationship determined by the problem, the solution is error-prone. Problem 1 The weather at a certain place is measured at four days in one day. They are: as early as 7 o’clock is minus 2.5 °C; 12 o’clock noon is 5.3 °C above zero; 7 o’clock in the evening is minus 1 °C; 2 o’clock in the morning is zero