小学数学简便计算

(18.1－13.93)×0.7
=(14+4.1-14+0.07)×0.7
=(4.1+0.07)×0.7
=4.1×0.7+0.07×0.7
=2.87+0.049
=2.919

(18.1－13.93)×0.7
=(14+4.1-14+0.07)×0.7
=4.17×0.7
=2.919

1.(18.1-13.93)*0.7
=4.17*0.7
=2.919
2.(18.1－13.93)×0.7
=(14+4.1-14+0.07)×0.7
=4.17×0.7
=2.919

（18.1-13.93）*0.7
=（18.1-14+0.07）*0.7
=4.17*0.7
=2.919

(18.1－13.93)×0.7
=(14+4.1-14+0.07)×0.7
=(4.1+0.07)×0.7
=4.1×0.7+0.07×0.7
=2.87+0.049
=2.919

直接计算，
第二个因数是一位小数，并且还是个纯小数，可以把它看成整数来算。