1/(1*3)+1/(3*5)+1/(5*7)+……+1/(99*101)
= 1/2 * (1-1/3) + 1/2 * (1/3-1/5) + 1/2 * (1/5-1/7) + .+ 1/2 * (1/99-1/101)
= 1/2 * (1 - 1/101)
= 50/101
1/(1*3)+1/(3*5)+1/(5*7)+……+1/(99*101)
= 1/2 * (1-1/3) + 1/2 * (1/3-1/5) + 1/2 * (1/5-1/7) + .+ 1/2 * (1/99-1/101)
= 1/2 * (1 - 1/101)
= 50/101