这种是采用乘法结合律，三个乘式都有1.37，所以为1.37×（0.46+0.46+0.08）＝1.37×1＝1.37。注意总结哦。
1.37×0.46+1.37×0.46+1.37×0.08=1.37x（0.46+0.46+0.08）=1.37x1=1.37
=1.37×（0.46+0.46+0.08）=1.37×1=1.37
