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\section{Ajouts de fractions}

Adding two fractions
\[
    A = \frac{- 2}{4} + \frac{7}{8}
\]
Solution 
\[
    \frac{- 2}{4} + \frac{7}{8}=\frac{- 2 \times 2}{4 \times 2} + \frac{7}{8}=\frac{- 4}{8} + \frac{7}{8}=\frac{- 4 + 7}{8}=\frac{3}{8}
\]

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