9分之7÷9分之5 10分之7×7分之5 8分之7×9分之1减8分之1÷9 怎么简便?
(7/9)÷(5/9)
=(7/9)*(9/5)
=7/5
(7/10)×(5/7)
=1/2
(7/8)×(1/9)-(1/8)÷9
=(7/8)×(1/9)-(1/8)×(1/9)
=[(7/8)-(1/8)]×(1/9)
=(3/4)×(1/9)
=1/12
9分之7÷9分之5 10分之7×7分之5 8分之7×9分之1减8分之1÷9 怎么简便?
(7/9)÷(5/9)
=(7/9)*(9/5)
=7/5
(7/10)×(5/7)
=1/2
(7/8)×(1/9)-(1/8)÷9
=(7/8)×(1/9)-(1/8)×(1/9)
=[(7/8)-(1/8)]×(1/9)
=(3/4)×(1/9)
=1/12