n: \(\dfrac{2}{7}+\dfrac{5}{7}\cdot\dfrac{14}{25}\)
\(=\dfrac{2}{7}+\dfrac{5}{25}\cdot\dfrac{14}{7}\)
\(=\dfrac{2}{7}+\dfrac{2}{5}=\dfrac{10+14}{35}=\dfrac{24}{35}\)
o: \(\dfrac{-4}{9}\cdot\dfrac{3}{8}+\dfrac{1}{18}=\dfrac{-4}{8}\cdot\dfrac{3}{9}+\dfrac{1}{18}\)
\(=\dfrac{-2}{3}+\dfrac{1}{18}=\dfrac{-12}{18}+\dfrac{1}{18}=-\dfrac{11}{18}\)
p: \(\dfrac{2}{7}+\dfrac{28}{27}:\dfrac{4}{9}\)
\(=\dfrac{2}{7}+\dfrac{28}{27}\cdot\dfrac{9}{4}\)
\(=\dfrac{2}{7}+\dfrac{9}{27}\cdot\dfrac{28}{4}=\dfrac{2}{7}+\dfrac{7}{3}=\dfrac{6+49}{21}=\dfrac{55}{21}\)
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