Решите примеры; 1) (х-2 3/7) + 4 5/21=1 5/42.

2) 22 - (х-3 3/4) = 28.

3) (х-5 3/8) - 2 7/16=-11 3/4.

4) (13 2/9+х) - 4 5/12=22 5/18.

1) (х - 2 3/7) + 4 5/21 = 1 5/42

х - 2 3/7 = 1 5/42 - 4 5/21 = 47/42 - 89/21 = (47-178) / 42 = - 131/42

х = - 131/42 + 2 3/7 = - 131/42 + 17/7 = (-131+102) / 42 = - 29/42

2) 22 - (х - 3 3/4) = 28

х - 3 3/4 = 22 - 28 = - 6

х = - 6 + 3 3/4 = - 2 1/4

3) (х - 5 3/8) - 2 7/16 = - 11 3/4

х - 5 3/8 = - 11 3/4 + 2 7/16 = - 47/4 + 39/16 = (-188+39) / 16 = - 149/16

х = - 149/16 + 5 3/8 = - 149/16 + 43/8 = (-149+86) / 16 = - 63/16 = - 3 15/16

4) (13 2/9 + х) - 4 5/11 = 22 5/18

13 2/9 - х = 22 5/18 + 4 5/12 = 22+4 + (5/18+5/12) = 26 + (10+15) / 36 = 26 25/36

х = 26 25/36 - 13 2/9 = 26-13 + (25/36 - 2/9) = 13 + (25-8) / 36 = 13 17/36