2分之1除以5分之4除以(9分之2×8分之3) (6分之5-4分之3)除以12分之5除以5分之9 都用简便计算

问题描述:

2分之1除以5分之4除以(9分之2×8分之3) (6分之5-4分之3)除以12分之5除以5分之9 都用简便计算

(1/2)/(4/5)/(2/9*3/8)
=(1/2)*(5/4)/(1/12)
=(5/8)*12
=15/2
(5/6-3/4)/(5/12)/(5/9)
=(5/6-3/4)/(5/12)*(9/5)
=(5/6-3/4)/(3/4)
=(5/6)*(4/3)-(3/4)*(4/3)
=10/9-1
=1/9