✿简算 ①18/11-﹙7/11+3/8﹚ ②7/9+3/10-2/9+17/10
问题描述：
✿简算 ①18/11-﹙7/11+3/8﹚ ②7/9+3/10-2/9+17/10
答
1.(18/11-7/11)-3/8
=1-3/8
=5/8
2.7/9+3/10-2/9+17/10
=(7/9-2/9)+(3/10+17/10)
=5/9+2
=23/9