Bonjour,
25 = 5 × 5
125 = 5 × 5 × 5
donc 25/125 = (5×5)/(5×5×5) = 1/5
456 ÷ 2 = 228
228 ÷ 2 = 114
114 ÷ 2 = 57
57 ÷ 3 = 19
donc 456 = 2 × 2 × 2 × 3 × 19
2 016 ÷ 2 = 1 008
1 008 ÷ 2 = 504
504 ÷ 2 = 252
252 ÷ 2 = 126
126 ÷ 2 = 63
63 ÷ 3 = 21
21 ÷ 3 = 7
donc 2016 = 2 × 2 × 2 × 2 × 2 × 3 × 3 × 7
donc 2016/456 = (2×2×2×2×2×3×3×7)/(2×2×2×3×19)
simplification par les chiffres soulignés
= (2×2×3×7)/19
= 84/19
