\(\frac{5}{6}+\frac{5}{12}+\frac{5}{20}+......+\frac{5}{110}\)
\(=\frac{5}{2.3}+\frac{5}{3.4}+\frac{5}{4.5}+..........+\frac{5}{10.11}\)
\(=5\left(\frac{1}{2.3}+\frac{1}{3.4}+\frac{1}{4.5}+..........+\frac{1}{10.11}\right)\)
\(=5\left(\frac{1}{2}-\frac{1}{3}+\frac{1}{3}-\frac{1}{4}+...........+\frac{1}{10}-\frac{1}{11}\right)\)
\(=5\left(\frac{1}{2}-\frac{1}{11}\right)\)
\(=5.\frac{9}{22}=\frac{45}{22}\)
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