a*b = a+b/2
a-b = 1
(1+b)*b = (1+b)+b/2
b+b² = 1+2b/2
2b+2b²/2 = 1+2b/2
2b+2b² = 1+2b
2b² = 1
b² = 1/2
b = 0,7071067811865475
a = 1+b
a = 1, 7071067811865475
1) 26*5=130-( 2 день)
2)130+26=156-(3день)
3)156+130+26=312-(за 3 дня)
ответ:312 билетов