Exercice 4 :
Explications étape par étape:
144/342 = 2×9×8/2×9×19 = 8/19
342/1260 = 9×2×19/9×2×70 = 19/70
1260/5700 = 3×3×4×5×7/3×4×5×95 = 21/95
342/5700 = 3×3×2×19/3×2×2×25×19 = 3/50
