解1题：2x÷(2/3)=5/

6 2x=2/3×5/

6 2x=5/9 x=5/9÷2 x=5/9×1/2 x=5/18 2题：(1/4)x×4/5=3/10 (1/4)x=3/10÷(4/5) (1/4)x=3/10×5/

4 (1/4)x=3/8 x=3/8÷(1/4) x=(3/8)×4 x=3/

2 3题：(5/6)x÷(2/3)=6/

7 (5/6)x=2/3×6/

7 (5/6)x=4/7 x=4/7÷(5/6) x=4/7×6/5 x=24/35 4题:(1/2)x×2/3=1/

6 (1/2)x=1/6÷(2/3) (1/2)x=1/6×3/

2 (1/2)x=1/4 x=1/4÷(1/2) x=(1/4)×2 x=1/

2 5题：(2/5)x÷(3/10)=20/51 (2/5)x=3/10×20/51 (2/5)x=2/17 x=2/17÷(2/5) x=2/17×5/2 x=5/17