(65/7+65/9)÷(5/7+5/9)脱式计算,能简算要简算,

问题描述:

(65/7+65/9)÷(5/7+5/9)脱式计算,能简算要简算,

(65/7+65/9)÷(5/7+5/9) =[65(1/7+1/9)]÷[5(1/7+1/9)] =65/5 =13