急需出30道六年级下册的比例方程并有答案

Answer 1

X:20=0.4:6
6X=20*0.4
X=4/3
45:9=x:3
32:4=X:8
38:60=x:30
25:40=x:60
11:50=x:100
18:25=x:75
85:1664=x:6124
14%:X=4.75:57/8
1) 3X-(1/2+1/4)=7/12
3X=7/12+3/4
3X=4/3
X=4/9
(2) 6.6-5X=3/4-4X
6.6-0.75=-4X+5X
X=5.85
(3) 1.1X+2.2=5.5-3.3X
1.1X+3.3X=5.5-2.2
4.4X=3.3
X=3/4=4/3