7/18*1/4+3/4*7/18 =7/18*(1/4+3/4)=7/18*1=7/18 这就是简便的算法了
应该是7/18*1/4+3/4*7/18=7/18*(1/4+3/4)=7/18*1=7/18
7/18*1/4+3/4÷18/7 =7/18*1/4+3/4*7/18=7/18*(1/4+3/4)=7/18*4=7/18
1/18*7/4+3/4*7/18=7/18*1/4+3/4*7/18=7/18*(1/4+3/4)=7/18
7/18乘以1/4加3/4乘7/18=7/18*(1/4+3/4)=7/18*1=7/18
7/18*1/4+3/4÷7/18 =7/72+27/14=1021/504
原式=7/18*1/4+3/4*76/18 =7/18*(1/4+3/4) =7/18*1 =7/18满意请及时采纳
4÷4/5-4/5÷4=5-1/5=4又4/57/18*1/4+3/4÷18/7 =7/18x1/4+3/4x7/18=7/18x(1/4+3/4)=7/18x1=7/18
7/18*1/4+3/4÷18/7 =7/18*1/4+3/4*7/18 =7/18*1/4+3/4 =7/18*1 =7/18,等于18分之7
=7/18 * (1/4)+3/4 * (7/18)=7/18 *(1/4+3/4)=7/18 *1=7/18望采纳