7.8乘0.75加上4.27除以1.4简便怎么计算
1个回答

7.8×0.75+4.27÷1.4

=3.9×2×0.75+4.27×5/7

=3.9×1.5+0.61×5

=3.9×1.5+6.1×0.5

=(3.9+6.1)×0.5+3.9×1

=5+3.9=8.9

------

7.8×0.75+4.27÷1.4

=7.8×0.75+4.27÷7÷0.2

=7.8×0.75+0.61÷0.2

= 3.9×1.5+0.61×5

= 3.9×1.5+6.1×0.5

=(3.9+6.1)×0.5+3.9×1

=5+3.9=8.9