8道简便计算题 现在要15+(-20)+6+(-8)(-7)+8+3+(-6)+(-5)+93 又3/5+4又8/5+(-5又2/3)+(-1/3)(-0.5)+2又1/4+(-9又1/2)+9.75-19+28+19+(-8)9+(-7)+10+(-3)+(-9)0.36+(-7.4)+0.3(-0.6)+0.643又1/4+(-5又2/3)+5又

来源:学生作业帮助网 编辑:作业帮 时间:2024/05/16 16:37:03

8道简便计算题 现在要
15+(-20)+6+(-8)
(-7)+8+3+(-6)+(-5)+9
3 又3/5+4又8/5+(-5又2/3)+(-1/3)
(-0.5)+2又1/4+(-9又1/2)+9.75
-19+28+19+(-8)
9+(-7)+10+(-3)+(-9)
0.36+(-7.4)+0.3(-0.6)+0.64
3又1/4+(-5又2/3)+5又3/4+(-8又2/5)

15+(-20)+6+(-8)
=(15+6)-(20+8)
=21-28
=-7
(-7)+8+3+(-6)+(-5)+9
=(8+3+9)-(7+6+5)
=20-18
=2
3 又3/5+4又8/5+(-5又2/3)+(-1/3)
=9又1/5-6
=3又1/5
(-0.5)+2又1/4+(-9又1/2)+9.75
=(2.25+9.75)-(0.5+9.5)
=12-10
=2
-19+28+19+(-8)
=(19-19)+(28-8)
=8
9+(-7)+10+(-3)+(-9)
=(9-9)+(10-7-3)
=0
0.36+(-7.4)+0.3(-0.6)+0.64
缺符号?0.3(-0.6)
3又1/4+(-5又2/3)+5又3/4+(-8又2/5)
=(3又1/4+5又3/4)-(5又2/3+8又2/5)
=9-14又1/15
=-5又1/15