1\/2+1\/3+1\/4+1\/5+...
1\/2+1\/3+1\/4+1\/5+1\/6+1\/7 =（1\/2+1\/3+1\/6）+（1\/4+1\/5+1\/7）=1+（9\/20+1\/7）=1+（63\/140+20\/140）=1+83\/140 =1又83\/140
1\/2+1\/3+1\/4+1\/5+1\/6等于几分之几
1\/2+1\/3+1\/4+1\/5+1\/6 =（1\/2+1\/3+1\/6）+0.25+0.2 =1+0.45 =1.45
2分之1+3分之1+4分之1+5分之1+6分之1+7分之1……简便方法计算
1\/2+1\/3+1\/4+1\/5+1\/6+1\/7 =(1\/2+1\/3+1\/6)+(1\/4+1\/5+1\/7)=(3+2+1)\/6+(35+28+20)\/140 =1+83\/140 即1又83\/140 或 =(140+83)\/140 =223\/140 【问题补充：主要方法，这个只是例题】主要方法就是分母有相同因子的先进行通分，比如本题中1\/2,1\/3,1\/6先通分计算，...
1\/2+1\/3+1\/4+1\/5+1\/6
解：1\/2+1\/3 = 5\/6,再和1\/6加，得到1，所以原式= 1 + 1\/4+1\/5 = 29\/20
计算:二分之一加三分之一加四分之一加五分之一加六分之一。
1\/2+1\/3+1\/4+1\/5+1\/6 =(1\/2+1\/3+1\/6)+(1\/4+1\/5)=(3\/6+2\/6+1\/6)+(5\/20+4\/20)=1+9\/20 =1又9\/20
1\/2+1\/3+1\/4+1\/5+1\/6+...+1\/n=?
首先因为1\/2 + 1\/3 = (2*3-1)\/(2*3)所以这些些全部得：(2*3*4*5*...-1)\/(2*3*4*5*...)
1\/2+1\/3+1\/4+1\/5+1\/6,用简便方法怎样计算
原式=5\/6+1\/4+1\/5+1\/6=1+1\/4+1\/5=1+9\/20
1\/2+1\/3+1\/4+1\/5+1\/6+1\/7+1\/8+1\/9+1\/10等于多少?
1\/2+1\/3+1\/4+1\/5+1\/6+1\/7+1\/8+1\/9+1\/10 =(1\/2+1\/3+1\/6)+(1\/4+1\/5+1\/10)+1\/7+1\/8+1\/9 =1+11\/20+1\/8+1\/7+1\/9 =1+27\/40+1\/9+1\/7 =1+283\/360+1\/7 =1+2341\/2520 =4861\/2520
1\/2+1\/3+1\/4+1\/5+1\/6+1\/12+1\/30 简便运算
1\/2+1\/3+1\/4+1\/5+1\/6+1\/12+1\/30 式中1\/6=（1\/2）-（1\/3）1\/12=（1\/3）-1\/4）1\/30=（1\/5）-（1\/6）所以1\/2+1\/3+1\/4+1\/5+1\/6+1\/12+1\/30=1\/2+1\/3+1\/4+1\/5+1\/2-1\/3+1\/3-1\/4+1\/5-1\/6=1\/2+1\/3+2\/5-1\/6=16\/15 ...
小学1\/2+1\/3+1\/4+1\/5+1\/6+...1\/n=?
1\/2+1\/3+1\/4+1\/5+1\/6+...1\/n =1-1\/2+1\/2-1\/3+1\/3-1\/4+1\/4-1\/5...+1\/(n-1)-1\/n =1-1\/n =(n-1)\/n
