Tìm n biết $\frac{1}{8}$+$\frac{1}{24}$+$\frac{1}{48}$+…+$\frac{1}{9800}$= $\frac{(n+5^{2})}{200}$

$\frac{1}{8}+\frac{1}{24}+\frac{1}{48}+…+\frac{1}{9800}=\frac{n+5^2}{200}$

$⇔\frac{1}{2.4}+\frac{1}{4.6}+\frac{1}{6.8}+…+\frac{1}{98.100}=\frac{n+25}{200}$

$⇔\frac{2}{2.4}+\frac{2}{4.6}+\frac{2}{6.8}+…+\frac{2}{98.100}=\frac{2.(n+25)}{200}$

$⇔\frac{1}{2}-\frac{1}{4}+\frac{1}{4}-\frac{1}{6}+\frac{1}{6}-\frac{1}{8}+…+\frac{1}{98}-\frac{1}{100}=\frac{n+25}{100}$

$⇔\frac{1}{2}-\frac{1}{100}=\frac{n+25}{100}$

$⇔\frac{49}{100}=\frac{n+25}{100}$

$⇔49=n+25$

$⇔n=24$

Vậy $n=24$.