`9/14 : 3/7 + 5/6 = 3/98 + 5/6 = 127/147`
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`4/7 xx (4 - 7/3) = 4/7 xx 5/3 = 20/21`
\(\dfrac{9}{14}:\dfrac{3}{7}+\dfrac{5}{6}=\dfrac{9}{14}\times\dfrac{7}{3}+\dfrac{5}{6}=\dfrac{3}{2}+\dfrac{5}{6}=\dfrac{7}{3}\)
\(\dfrac{4}{7}\times\left(4-\dfrac{7}{3}\right)=\dfrac{4}{7}\times\dfrac{5}{3}=\dfrac{20}{21}\)
\(=\dfrac{3\times3}{2\times7}\times\dfrac{7}{3}+\dfrac{5}{6}=\dfrac{3}{2}+\dfrac{5}{6}=\dfrac{9}{6}+\dfrac{5}{6}=\dfrac{14}{6}=\dfrac{7}{3}\)
b)\(=\dfrac{4}{7}\times\dfrac{5}{3}=\dfrac{20}{21}\)