先算1/6×3/10×5/1约分后=1/4
½-1/4
=¼
-0.5
1\/2-1\/6ⅹ3\/10÷1\/5等于多少?
解题过程:1\/2-1\/6×3\/10÷1\/5 =1\/2-1\/6×3\/10×5 =1\/2-3\/6×5\/10 =1\/2-1\/2×1\/2 =1\/2
(1\/2-1\/6)x3\/5÷1\/5
(1\/2—1\/6)x3\/5➗1\/5(先做小括号)=(3\/6—1\/6)x3\/5➗1\/5 =1\/3x3\/5x5 =1
(1\/2-1\/6)x3\/5简便计算?
(1\/2-1\/6)x3\/5 =1\/2x3\/5-1\/6x3\/5 =3\/10 -1\/10 =2\/10 =1\/5
-1\/2减1\/6减1\/12减……减1\/90=多少
=-1\/2-1\/2+1\/3-1\/3+1\/4-1\/4+1\/5-...-1\/9+1\/10 =-1+1\/10 =-9\/10
1\/2-1\/6-1\/12-1\/20简便计算谢谢
1\/2-1\/6-1\/12-1\/20简便计算 解析:1\/2-1\/6-1\/12-1\/20 =1\/2-(1\/2-1\/3)-(1\/3-1\/4)-(1\/4-1\/5)=1\/2-1\/2+1\/3-1\/3+1\/4-1\/4+1\/5 =(1\/2-1\/2)+(1\/3-1\/3)+(1\/4-1\/4)+1\/5 =1\/5
5分之3除以5分之6-3x=5分之1 (解方程)
回答:一个数的12分之5等于6分之5的2倍,求这个数。用方程
一筐苹果卖掉1\/5后,又卖掉6kg,这时卖出的质量正好是原来苹果的1\/2,这...
20千克。解题过程,1\/5也等于2\/10,先卖掉1\/5,再卖掉6千克,卖出的部分是原来苹果的1\/2,那么6千克就是,1\/2减去1\/5,等于3\/10,那么原来苹果的重量为,用6千克除以3\/10,等于20千克。
1\/5加1\/2等于多少?1\/2减1\/3等于多少?1\/2加1\/3等于多少?
回答:1\/5+1\/2 =(2+5)\/10 =7\/10 1\/2-1\/3 =(3-2)\/6 =1\/6 1\/2+1\/3 =(3+2)\/6 =5\/6
先观察下面的算式,你发现了什么?2×1\/3=1\/2-1\/3 3×1\/4=1\/3-1\/4 4...
我发现:1\/[n(n+k)]=1\/k×[1\/n-1\/(n+k)](n,k均为正整数)
1\/2+1\/6+1\/12+...+1\/90。怎么简便计算?
1\/2+1\/6+1\/12+……+1\/90简便计算。”解析:观察所给算式,各项分母可以拆分为 1×2, 2×3,3×4,4×5……9×10,据此可以将各项加数进行拆分,从而达到简化计算的目的。解答:1\/2+1\/6+1\/12+……+1\/90 =(1-1\/2)+(1\/2-1\/3)+(1\/3-1\/4)+……(1\/9-1\/10)=1-1\/2+...