Câu hỏi 25
Giá trị của biểu thức sau bằng bao nhiêu?
$$\begin{aligned}&\left(\frac12+\frac13+\frac14+\frac15+\cdots+\frac1{37}\right)+\left(\frac23+\frac24+\frac25+\cdots+\frac2{37}\right)\\&\quad+\left(\frac34+\frac35+\frac36+\cdots+\frac3{37}\right)+\cdots+\left(\frac{35}{36}+\frac{35}{37}\right)+\frac{36}{37}.\end{aligned}$$
$$\begin{aligned}&\left(\frac12+\frac13+\frac14+\frac15+\cdots+\frac1{37}\right)+\left(\frac23+\frac24+\frac25+\cdots+\frac2{37}\right)\\&\quad+\left(\frac34+\frac35+\frac36+\cdots+\frac3{37}\right)+\cdots+\left(\frac{35}{36}+\frac{35}{37}\right)+\frac{36}{37}.\end{aligned}$$