16. Скорочення дробів - 17. Зведення дробі » 661

Скороти дріб поступово, користуючись ознаками подільності: 30/42 = (30 ∶ 2)/(42 ∶ 2) = (15 ∶ 3)/(21 ∶ 3) = 5/7. 24/56 = (24 ∶ 2)/(56 ∶ 2) = (12 ∶ 2)/(28 ∶ 2) = (6 ∶ 2)/(14 ∶ 2) = 3/7. 54/90 = (54 ∶ 2)/(90 ∶ 2) = (27 ∶ 3)/(45 ∶ 3) = (9 ∶ 3)/(15 ∶ 3) = 3/5. 90/72 = (90 ∶ 2)/(72 ∶ 2) = (45 ∶ 3)/(36 ∶ 3) = (15 ∶ 3)/(12 ∶ 3) = 5/4. 81/54 = (81 ∶ 3)/(54 ∶ 3) = (27 ∶ 3)/(18 ∶ 3) = (9 ∶ 3)/(6 ∶ 3) = 3/2. 84/120 = (84 ∶ 2)/(120 ∶ 2) = (42 ∶ 2)/(60 ∶ 2) = (21 ∶ 3)/(30 ∶ 3) = 7/10. 200/240 = (200 ∶ 2)/(240 ∶ 2) = (100 ∶ 2)/(120 ∶ 2) = (50 ∶ 2)/(60 ∶ 2) = (25 ∶ 5)/(30 ∶ 5) = 5/6. 162/270 = (162 ∶ 2)/(270 ∶ 2) = (81 ∶ 3)/(135 ∶ 3) = (27 ∶ 3)/(45 ∶ 3) = (9 ∶ 3)/(15 ∶ 3) = 3/5. 243/810 = (243 ∶ 3)/(810 ∶ 3) = (81 ∶ 3)/(270 ∶ 3) = (27 ∶ 3)/(90 ∶ 3) = (9 ∶ 3)/(30 ∶ 3) = 3/10.