Question

初一有理数分数加减法混合运算，要例题和答案。拜托了！

要十道

Answer 1

（-0.8）+1.2+（-0.7）+（-2.1）+0.8+3.5
=(-0.8+0.8)+(1.2+3.5-0.7)-2.1
=4-2.1
=1.9

1/2+（-2/3）+4/5+（-1/2）+（-1/3）
=(1/2-1/2)+4/5-(2/3+1/3)
=4/5-1
=-1/5

-4.2+5.7-8.4+10
=(5.7+10)-(4.2+8.4)
=15.7-12.6
=3.1

-1/4+5/6+2/3-1/2
=(5/6+2/3)-(1/4+1/2)
=(5/6+4/6)-(1/4+2/4)
=9/6-3/4
=3/2-3/4
=6/4-3/4
=3/4

Answer 2

1/3-2/5+2/15=1/15
4/7+(-3/4)+1/2=9/28
-5/8+(1/2-1/4)=-3/8
-11/3+7/15+8/5=8/5
12/7+4/9-5=-179/63
12-112/3+5/6=-49/2
19/2+(-18)+(-14/3)=-79/6
5+5/12+7/3=31/4
8/7-11/21-7/3=-12/7
31/11-5+14/3=82/33

Answer 3

4/2-5/9+3/7
你自己慢慢算，其实还蛮简单的(⊙o⊙)哦!