\(\frac{3}{1.2}+\frac{3}{2.3}+\frac{3}{3.4}+....+\frac{3}{49.50}\)
\(=3.\left(\frac{1}{1.2}+\frac{1}{2.3}+\frac{1}{3.4}+...+\frac{1}{49.50}\right)\)
\(=3.\left(1-\frac{1}{2}+\frac{1}{2}-\frac{1}{3}+...+\frac{1}{49}-\frac{1}{50}\right)\)
\(=3.\left(1-\frac{1}{50}\right)\)
\(=3.\frac{49}{50}=\frac{147}{50}\)
3/1.2+3/2.3+3/3.4+...+3/49.50
\(=3\cdot\left(\frac{1}{1\cdot2}+\frac{1}{2\cdot3}+...+\frac{1}{49\cdot50}\right)\)
\(=3\cdot\left(1-\frac{1}{2}+\frac{1}{2}-\frac{1}{3}+...+\frac{1}{49}-\frac{1}{50}\right)\)
\(=3\cdot\left(1-\frac{1}{50}\right)\)
\(=3\cdot\frac{49}{50}\)
\(=\frac{147}{50}\)
3/1.2 + 3/2.3 + 3/3.4 + ..... + 3/49.50
= 3/1 - 3/2 + 3/2 - 3/3 + 3/3 - 3/4 + ........... + 3/49 - 3/50
= 3/1 - 3/50
= 147/50
