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\section{Ajouts de fractions}

Adding two fractions
\[
    A = \frac{8}{9} + \frac{3}{63}
\]
Solution 
\[
    \frac{8}{9} + \frac{3}{63}=\frac{8 \times 7}{9 \times 7} + \frac{3}{63}=\frac{56}{63} + \frac{3}{63}=\frac{56 + 3}{63}=\frac{59}{63}
\]

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