1x2/1+2x3/1+3x4/1+4x5/1+...23x24/1 =一乘二分之一...

1x2/1+2x3/1+3x4/1+4x5/1+...23x24/1
=1-1/2+1/2-1/3+1/3-1/4+1/4-1/5+……+1/23-1/24
=1-1/24
=23/24

1x2/1+2x3/1+3x4/1+4x5/1+...23x24/1
=1-1/2+1/2-1/3+1/3-1/4+1/4-1/5+……+1/23-1/24
=1-1/24
=23/24

这是什么题啊！

1*1/2+2*1/3+3*1/4+4*1/5……+23*1/24
=1-1/2+1/2-1/3+1/3-1/4+1/4-1/5……+1/23-1/24
=1-1/24
=23/24
题目应该是这个意思吧。