\frac{5}{12}=\frac{1}{4}+\frac{1}{x}
\frac{5}{12} = \frac{3}{12}+\frac{2}{12}
\frac{5}{12}=\frac{1}{4}+\frac{1}{6}
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\frac{31}{30}=\frac{1}{5}+\frac{1}{3}+\frac{1}{x}
\frac{31}{30}=\frac{6}{30}+\frac{10}{30}+\frac{15}{30}
\frac{31}{30}=\frac{1}{5}+\frac{1}{3}+\frac{1}{2}
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