3.7×7.3_7.3用简便方法计算是什么3.7×7.3_7.3=7.3*（3.7-1）=3.7*2.7=9.99
3.7×7.3-7.3=(3.7-1)*7.3=2.7*7.3=(3-0.3)*7.3=21.9-2.19=19.71
