脱式计算(1-5/1÷10/9)÷20/3,上面一步写完是直接写9/7÷20/3,还是(1-5/1x9/10)÷20/3
2个回答

(1-5/1÷10/9)÷20/3 把括号里面分数的除法变成乘法来做,最好不要省略步骤

=(1-5/1×9/10)÷20/3

=(1-9/2)÷20/3

=9/7÷20/3

=9/7×3/20

=27/140

9/8×[4/3-(16/7-4/1)] 按照四则混合运算的规则来运算,最好不要省略步骤

=9/8×[4/3-(16/7-16/4)]

=9/8×(4/3-16/3)

=9/8×(16/12-16/3)

=9/8×16/9

=16/8

=2/1

15÷20℅ 最好不要直接写出得数,计算要有计算的步骤

=15×20/100

=15×5

=75