5/8+×=11/12 2X–1/9 =8/9
3X–1.4×2=1.1 X+2/3–1/2=17/18
5.5x–3x = 1.75 X+3/5 =7/10
5X = 40/8 X÷2/3 =5/6
X–3/4X =1/8 X+2/7X = 18
12X = 15×3/5/25 X×（1/6+3/8）=13/12
X×（1+1/4）= 25 （1–5/9）X =8/15
X×4/5× 1/8= 10 X×2/3= 8×3/4
X×2/7 = 8/21 15÷X =5/6