$\textit{Đáp án + Giải thích các bước giải:}$
$\text{A = $\dfrac{1}{100}$ - $\dfrac{1}{100.99}$ - $\dfrac{1}{99.98}$ + }$
$\text{A = $\dfrac{1}{100}$ - $\bigg(\dfrac{1}{1} - \dfrac{1}{2} + \dfrac{1}{2} - \dfrac{1}{3} + … + \dfrac{1}{99} - \dfrac{1}{100}\bigg)$}$
$\text{A = $\dfrac{1}{100}$ - $\bigg(1 - \dfrac{1}{100}\bigg)$}$
$\text{A = $\dfrac{1}{100}$ - $\dfrac{-99}{100}$}$
$\text{A = $\dfrac{-49}{50}$}$
