1/(1*4)+1/(4*7)+1/(7*10)+……+1/(97*100)=(1-1/4)/3+(1/4-1/7)/3+(1/7-1/10)/3+……+(1/97-1/100)/3=(1-1/4+1/4-1/7+1/7-1/10+……+1/97-1/100)/3=(1-1/100)/3=33/100应该就是这样了
