Simplifie les fractions suivantes : \[\Eqalign{ \frac9{12}&\kern5mm&\frac{56}{72}&\kern5mm& \frac5{30}&\kern5mm&\frac{24}{36}&\kern5mm& \frac8{18}&\kern5mm&\frac{39}{30}&\kern5mm& \frac{60}{35}&\kern5mm&\frac{45}{27}\cr }\]