(1/4 + 1/5 x= 1 4/5, ( 3 1/8 + 1

1

1/5 х = 1 4/5 - 1/4;

1/5 х = 9/5 - 1/4;

1/5 х = (9 * 4 - 1 * 5)/20;

1/5 х = (36 - 5)/20;

1/5 х = 31/20;

х = 31/20 : 1/5;

х = 31/20 * 5/1;

х = 31/4;

х = 7 3/4.

Ответ: 7 3/4.

2

(25/8 + 7/4) х = 13/6;

(28 * 1 + 7 * 2)/8 х = 13/6;

(28 + 14)/8 х = 13/6;

42/8 х = 13/6;

х = 13/6 : 42/8;

х = 13/6 * 8/42;

х = 13/3 * 2/21;

х = 26/63.

Ответ: 26/63.

3

(25/12 - 11/6) х = 3/4;

(25 * 1 - 11 * 2)/12 х = 3/4;

(25 - 22)/12 х = 3/4;

3/12 х = 3/4;

х = 3/4 : 1/4;

х = 3/4 * 4/1;

х = 3.

Ответ: 3.