运用加法交换律,5/9+4/9+7/12=1+7/12=12/12+7/12=19/12,得出算式的答案为19/12
5/9加7/12加4/9减1/12简单计算5/9+7/12+4/9减去1/12简易计算5/5+7/2+4/1/125/9+4/12+(7/12-1/12)=1+1/2=3/2
答:5/9+7/12+4/9=5/9+4/9+7/12=9/9+7/15=1+7/12=12/12+7/12=19/12
答:
5/9+7/12+4/9
=5/9+4/9+7/12
=9/9+7/12
=1+7/12
=12/12+7/12
=19/12