Question

4         4                  4

----  +  ------ +  ...   +       ------

5.8    8.11              47.50

 

Answer 1

\(\frac{4}{5.8}+\frac{4}{8.11}+...+\frac{4}{47.50}\)

\(\Rightarrow\frac{4}{3}\left(\frac{3}{5.8}+\frac{3}{8.11}+...+\frac{3}{47.50}\right)\)

\(\Rightarrow\frac{4}{3}\left(\frac{1}{5}-\frac{1}{8}+...+\frac{1}{47}-\frac{1}{50}\right)\)

\(\Rightarrow\frac{4}{3}\left(\frac{1}{5}-\frac{1}{50}\right)\)

\(\Rightarrow\frac{4}{3}.\frac{9}{50}=\frac{6}{25}\)