Уравнение 4/7x=1; 3/4x=12; x: 7/15=15/28

1) 4/7х = 1

   7х = 4

   х = 4/7

2) 4х = 12

    х = 12:4

    x = 3

3)  x : 7/15 = 15/28

    x = 15/28 * 7/15

    x = 1/4

4/7х = 1

х= 1:4/7 = (1*7/4)

х = 7/4

3/4х =12

х= 12:3/4 = (12* 4/3)

х= 16

х:7/15 =15/28

х= 15/28 * 7/15

х= 1/4