(x-1):12=4.5:5.4 2.5:x=0.2:40% x-9分之4X=250

问题描述:

(x-1):12=4.5:5.4 2.5:x=0.2:40% x-9分之4X=250

(x-1):12=4.5:5.4
(x-1):12=5:6
6(x-1)=12*5
6(x-1)=60
x-1=10
x=11
2.5:x=0.2:40%
0.2x=2.5*40%
0.2x=1
x=1/0.2
x=5
x-9分之4X=250
5x/9=250
x=250*9/5
x=450