简便计算:13/15*2/9+7/15*13/9
问题描述:
简便计算:13/15*2/9+7/15*13/9
答
13/15*2/9+7/15*13/9
=13/15*2/9+13/15*7/9
=13/15*(2/9+7/9)
=13/15