24*60=1440
1440*2=2880
Ответ: 2880 секунд
2_2/3 = 8/3
по свойству пропорции получим:
9х = 4у
8у = 45z ---> 45z = 18x
y = (9/4)x
z = (18/45)x = (2/5)x
x + (9/4)x + (2/5)x = 219
20x + 45x + 8x = 219*20
x = 219*20/73 = 60
у = 9*60/4 = 9*15 = 135
z = 2*60/5 = 2*12 = 24
24+135+60 = 219
60/135 = 4/9
135/24 = 45/8 ---15 : 2_2/3 = 15 : 8/3 = 45/8