1 4 1 13
18 - 3 - x = 5 + 3
4 14 14 14
3 14
15 - x = 8
28 14
3
x = 15 - 9
28
x = 6
P.S.
18 1/4 - 3 4/14 = (18-3)+(1/4-4/14)=(18-3)+(7-4/28) = 15 3/28
по-моему так
1 4 1 13
18 - 3 - x = 5 + 3
4 14 14 14
3 14
15 - x = 8
28 14
3
x = 15 - 9
28
3
x = 6
28
P.S.
18 1/4 - 3 4/14 = (18-3)+(1/4-4/14)=(18-3)+(7-4/28) = 15 3/28
по-моему так