1、(-8)+(2又1/2)+2+(-1/2)+12 = - 16/2 + 5/2 + 4/2 - 1/2 +24/2=16/2 = 8
2、(-1/3)+(+1/2)+(-2/3)+(+4/5)+(1/2)= - 10/30 + 15/30 - 20/30 + 24/30 + 15/30= 24/30 = 4/5
3、-5.3-3.2+2.5-|-5.7|= - 8.5 + 2.5 - 5.7 = - 6 - 5.7 = - 11.7
4、6又3/5+24+4又2/5-14-8.8-1.2 =(6又3/5+4又2/5)+(24-14)-(8.8+1.2)=11+10-10=11
5、(-20)-(+5)-(-5)-(-13) = - 20 - 5 + 5 + 13 = - 25 + 5 +13 = - 20 + 13 = - 7
6、(-2又1/6)+5又1/11+(-4又5/6)+(-25又1/11)=(-2又1/6 - 4又5/6)+(5又1/11 - 25又1/11)= - 7 - 20 = -27
7、(-1/2)-(-1/3)-(-1/4)-(-1/6) = - 6/12 + 4/12 + 3/12 + 2/12 = 3/12 = 1/4
8、 2-5/12-5/18+1/12-7/18-2又8/17 = (2 - 2又8/17)-(5/12 - 1/12)-(5/18 + 7/18)
= - 8/17 - 4/12 - 12/18 = - 8/17 - 1/3 - 2/3 = - 8/17 -1 = -1又8/17
9、6又1/4-3.4-(-6)-(-2又3/4)+4+3.4 =(6又1/4 + 2又3/4)-(3.4 - 3.4)+(6 + 4)
= 9 - 0 + 10 = 19
10、-1/5+0.6-(2又2/15-1又3/10)= - 6/30 + 18/30 - 2又4/30 + 1又9/30 = - 1又17/30
辛辛苦苦写了这么多,没有功劳也有苦劳,希望采纳哦~
题的步骤我也写了,希望你能自己做一遍再来对下答案
这些是最基本的,多看书上的例题,最好自己钻研一下,这样才能自己真正地掌握. 例如(3)=-8.5+2.5-5.7=-11.7 (4)=11
11
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