Question

a) 2/3+7/5;   7/5-1/4:2/3;    6/13×2:18/13

Answer 1

\(a,\dfrac{2}{3}+\dfrac{7}{5}=\dfrac{10}{15}+\dfrac{21}{15}=\dfrac{31}{15}\)

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\(\dfrac{7}{5}-\dfrac{1}{4}:\dfrac{2}{3}=\dfrac{7}{5}-\dfrac{1}{4}\times\dfrac{3}{2}=\dfrac{7}{5}-\dfrac{3}{8}=\dfrac{56}{40}-\dfrac{15}{40}=\dfrac{41}{40}\)

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\(\dfrac{6}{13}\times2:\dfrac{18}{13}=\dfrac{12}{13}:\dfrac{18}{13}=\dfrac{12}{13}\times\dfrac{13}{18}=\dfrac{12}{18}=\dfrac{2}{3}\)

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