2⼀9×7⼀15+2⼀15×8⼀9怎么用简便方法算?

2025-06-26 11:33:22
推荐回答(2个)
回答1:

原式=7/9x2/15+2/15x8/9
=2/15x(7/9+8/9)
=2/15x15/9
=2/9

回答2:

2/9×7/15+2/15×8/9
=2/9×7/15+2/9×8/15
=2/9×(7/15+8/15)
=2/9×1
=2/9