Bonjour,
1) 560 ÷ (1 + 7) × 7 = 490 (mL)
2) oui car 330 ÷ (1 + 3 + 7) × 7 = 210
3) 54 × 16/9 = 114 (cm)
4) 350 ÷ (5 + 2) × 5 = 250 maillots noirs
350 ÷ (5 + 2) × 2 = 100 maillots rouges