6.4*99=的简便算法
来源:学生作业帮助网 编辑:作业帮 时间:2024/10/04 12:41:15
65.25/75+2.98*99=65.25÷5÷15+2.98*(100-1)=13.05÷5÷3+2.98*100-2.98=2.61÷3+298-2.98=0.87-2.98+298=298-2
56*99=56*(100-1)=56*100-56*1=5600-56=5544
100×3-3
8.6×99+8.6=8.6x(99+1)=8.6x100=860
5✘99+5=5✘(99+1)=5✘100=500再答:祝你学习进步!再答:不懂得可以问我再答:望采纳!
=640/25=640/(5*5)=(640/5)/5=128/5=25.6
53*99*25=(50+3)*(100-1)*25=(5000-50+300-3)*25=125000+7500-1250-75=131175
54*99*99+45=540000-10800+54+45=539299
99×999=99×(1000-1)=99000-99=99000-100+1=98900+1=98901
456×99=456×(100-1)=456×100-456=45600-456=45144
0.01+1.01×99=0.01+(1+0.01)×99=0.01+99+0.01×99=99+0.01+0.01×99=99+0.01×(1+99)=99+0.01×100=99+1=1
4.8*99*48=48*48*9.9=(46+2)*(50-2)*9.9=(46*50+2*(50-46)-4)*9.9=(2300+8-4)*9.9=2304*(10-0.1)=23040-230
99*99+99=99*(99+1)=99*100=9900再问:756.25+27又5分之4-(7又5分之4+56又4分之1)再答:=756.25+27又4/5-7又4/5-56-0.25=(756
101×99=(100+1)x(100-1)=100^2-1^2=10000-1=9999
(100-1)*(100+1)=100*100-1*1=9999
1.25*6.4=0.125*64=1/8*8*8=8
1.25×(8×0.8)=1.25×8×0.8=10×0.8=8
138(99+1)=138X100=13800