1+1/2)*(1+1/3)*(1+1/4)*......*(1+1/98)*(1+1/99)

* Hướng dẫn giải

=$\frac{3}{2}$ x $\frac{4}{3}$ x $\frac{5}{4}$ x.... x $\frac{99}{98}$ x $\frac{100}{99}$

= $\frac{100}{2}$=50