Verified answer

1 11/14 : 2 1/7 * 12/35 = 2/7

1) 1 11/14 : 2 1/7 = 25/14 : 15/7 = 25/14 * 7/15 = 25/30 = 5/6

2) 5/6 * 12/35 = 2/7

4 4/9 : (2/3х + 14) = 5/27

2/3х + 14 = 4 4/9 : 5/27 = 40/9 : 5/27 = 40/9 * 27/5 = 8 * 3 = 24

2/3х = 24 - 14

2/3х = 10

х = 10 : 2/3 = 10 * 3/2 = 30/2 = 15

х = 15

1) 5 5/6 : 7 = 35/6 * 1/7 = 5/6 км дороги прокладывают за 1 день

2) 9 1/6 : 5/6 = 55/6 * 6/5 = 55/5 = 11 дней 

Ответ: 9 1/6 км дороги смогут проложить за 11 дней.