看好了:8/9*4/5+8/9*2/5-8/9
=8/9*(4/5+2/5)-8/9
=8/9*6/5-8/9
=8/9*6/5-8/9*1
=8/9*(6/5-1)
=8/9*1/5
=8/45 绝对准确!
望采纳
8/9*4/5+8/9*2/5-8/9
=8/9*(4/5+2/5)-8/9
=8/9*5/6-8/9
=8/9*(6/5-1)
=8/9*1/5
=8/45
简单!8/9×4/5+8/9×5/2-8/9
=8/9×(4/5+2/5-1)
=8/9×1/5
=8/45