一又,2⼀7乘5⼀7加5⼀7,乘5⼀11减5⼀7用简便方法计算,i

2025-02-25 15:26:49
推荐回答(1个)
回答1:

  • 解析:

  (1+2/7)×(5/7)+5/7

  =(9/7)×(5/7)+(5/7)×1

  =(5/7)×(16/7)

  =80/49