1、每份數(shù)×份數(shù)＝總數(shù)總數(shù)÷每份數(shù)＝份數(shù)總數(shù)÷份數(shù)＝每份數(shù)

　　2、1倍數(shù)×倍數(shù)＝幾倍數(shù)幾倍數(shù)÷1倍數(shù)＝倍數(shù)幾倍數(shù)÷倍數(shù)＝1倍數(shù)

　　3、速度×時間＝路程路程÷速度＝時間路程÷時間＝速度

　　4、單價×數(shù)量＝總價總價÷單價＝數(shù)量總價÷數(shù)量＝單價

　　5、工作效率×工作時間＝工作總量工作總量÷工作效率＝工作時間工作總量÷工作時間＝工作效率

　　6、加數(shù)＋加數(shù)＝和和－一個加數(shù)＝另一個加數(shù)

　　7、被減數(shù)－減數(shù)＝差被減數(shù)－差＝減數(shù)差＋減數(shù)＝被減數(shù)

　　8、因數(shù)×因數(shù)＝積積÷一個因數(shù)＝另一個因數(shù)

　　9、被除數(shù)÷除數(shù)＝商被除數(shù)÷商＝除數(shù)商×除數(shù)＝被除數(shù)