7/9 / 11/5 + 2/9 * 5/11 简便算

问题描述:

7/9 / 11/5 + 2/9 * 5/11 简便算

7/9 / 11/5 + 2/9 * 5/11
=7/9*5/11+2/9*5/11
=(7/9+2/9)*5/11
=1*5/11
=5/11