1/(1*4)+1/(4*7)+1/(7*10)+……+1/(97*100)

问题描述:

1/(1*4)+1/(4*7)+1/(7*10)+……+1/(97*100)

1/(1*4)+1/(4*7)+1/(7*10)+……+1/(97*100)
=1/3(1-1/4+1/4-1/7+.+1/97-1/100)
=1/3(1-1/100)
=33/100