\(A=\dfrac{1}{5.6}+\dfrac{1}{6.7}+\dfrac{1}{7.8}+\cdot\cdot\cdot+\dfrac{1}{24.25}\)
\(A=\dfrac{1}{5}-\dfrac{1}{6}+\dfrac{1}{6}-\dfrac{1}{7}+\dfrac{1}{7}-\dfrac{1}{8}+\cdot\cdot\cdot+\dfrac{1}{24}-\dfrac{1}{25}\)
\(A=\dfrac{1}{5}-\dfrac{1}{25}\)
\(A=\dfrac{5}{25}-\dfrac{1}{25}\)
\(A=\dfrac{4}{25}\)
\(B=\dfrac{2}{1.3}+\dfrac{2}{3.5}+\dfrac{2}{5.7}+\cdot\cdot\cdot+\dfrac{2}{99.101}\)
\(B=\dfrac{1}{1}-\dfrac{1}{3}+\dfrac{1}{3}-\dfrac{1}{5}+\dfrac{1}{5}-\dfrac{1}{7}+\cdot\cdot\cdot+\dfrac{1}{99}-\dfrac{1}{101}\)
\(B=\dfrac{1}{1}-\dfrac{1}{101}\)
\(B=\dfrac{101}{101}-\dfrac{1}{101}\)
\(B=\dfrac{100}{101}\)
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