\(\frac{2}{1.4}+\frac{2}{4.7}+\frac{2}{7.9}+...+\frac{2}{196.199}=\frac{2}{3}\left(\frac{3}{1.4}+\frac{3}{4.7}+\frac{3}{7.9}+...+\frac{3}{196.199}\right)\)
\(=\frac{2}{3}\left(1-\frac{1}{4}+\frac{1}{4}-\frac{1}{7}+\frac{1}{7}-\frac{1}{9}+...+\frac{1}{196}-\frac{1}{199}\right)\)
\(=\frac{2}{3}\left(1-\frac{1}{199}\right)\)
\(=\frac{2}{3}.\frac{198}{199}\)
\(=\frac{132}{199}\)
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