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用简便方法计算下面各题,急0.8888*10.4-0.1111*3.2(36963-369.63)/(24642-246.42)(1+1.8)+(2+1.8*2)+(3+1.8*3)+···+(100+1.8*100)(2.17+5.49+3.81)*(5.49+2.17+9.2)-(3.18+2.7+5.49+9.2)*(2.17.5.49)

题目详情
用简便方法计算下面各题,急
0.8888*10.4-0.1111*3.2
(36963-369.63)/(24642-246.42)
(1+1.8)+(2+1.8*2)+(3+1.8*3)+···+(100+1.8*100)
(2.17+5.49+3.81)*(5.49+2.17+9.2)-(3.18+2.7+5.49+9.2)*(2.17.5.49)
▼优质解答
答案和解析
1、0.8888*10.4-0.1111*3.2=0.8888*10.4-0.8888*0.4=0.8888*(10.4-0.4)=8.888
2、(36963-369.63)/(24642-246.42)=[369.63*(100-1)]/[246.42*(100-1)]
=369.63/246.42(扩大100倍再约9、37)
=111/74
3、(1+1.8)+(2+1.8*2)+(3+1.8*3)+···+(100+1.8*100)
=(1+2+3+…+100)+(1.8*1+1.8*2+1.8*3+…1.8*100)
=5050+1.8*(1+2+3+…+100)
=5050+1.8*5050
=5050*(1+1.8)
=5050*2.8
=14140
4、再核对下是不是数字打错了?