x：1.2=5:2 2x:0.6=1.8:6 3/5:0.9=x:10 x:3/4=5/12:3/8 3/5:X=1/4:0.75 5/14:3/10=x x:4.5=12:0.9 1/5:0.5=3:X 1.6:X=1/8:0.5 X:12=7/4:28 4/7:X=2/3:1/2 3.5:0.4=x:1.2 3/10:X=3/4:9/8 X:30%=9:10% 4:X=4/7:8/7 X:10=0.1:2 25:0.25=X:1.6 0.8:4=X:8 4/5:X=7/8:5/8 X:10=6:12 1.8:X=3.6:0.6 5/9:1/6=x:12/5 3/4:X=7/8:14 2.4:X=12:2/3 X:25=450:5 19.5:X=2.4:3 X:4=10.8:6 100-10:100-15=100-X X:7/9=4.2:7/9 1/10:1X=3:2 35:35 X=18-3:18
30道純自編無抄襲