2/5×1/4×5/6
___________
2/3×6/7×7/8
2)1/3×1/4×1/2
__________
5/6×2/3×1/12
3)5/9×1/6×5/18
____________
1/18×2/3×1/9
4)3/5×2/15×1/12
_____________
1/6×2/5×3/10