9/2×5/3 7/6×9/7 8/5×15/4 20/9×21/5
问题描述：
9/2×5/3 7/6×9/7 8/5×15/4 20/9×21/5
9/2×5/37/6×9/7 8/5×15/4
20/9×21/55/6×3/5 25/7×14/15
11/3×2/1 50/19×19/10
答
2/152/3628/31/210/322/35