1/х +1/3/4 х=7/121/х+1/4х=3/81/2х+7/5х=6 1/3

1/х +1 :3/4 х=7/12
3/4       1
---- х+ ----- х=7/12
3/4      3/4

7/4
----- х =7/12
3/4

(7/4*4/3)*х=7/12
7/3х=7/12
х=7/12:7/3
х=7/12*3/7
х=3/12
х=1/4

1/х+1/4х=3/8
4/4х+1/4х=3/8
5/4х=3/8
х=3/8:5/4
х=3/8*4/5
х=3/10

1/2х+7/5х=6 1/3
5/10х+14/10х=19/3
19/10х=19/3
х=19/3:19/10
х=19/3*10/19
х=10/3
х=3 1/3