分数加、减法练习(1)1:
7/12 1/12 12/35 2/3513/36 5/36 17/72 1/722:79/90 23/42 4/9 23/403:+ - - - + +4:1/2+x=5/6 x=5/6-1/2 x=1/3 x+1/4=1/2 x=1/2-1/4 x=1/4 x-2/3=1/4 x=2/3+1/4 x=11/125: 3/7-1/3=2/216: ⑴2/5+1/4 =8/20+5/20 =13/20米 ⑵2/5+13/20 =8/20+13/20 =21/20米7:⑴知识之窗、美文欣赏都 |