3 9/14 х
----------- = --------
2 1/7 1,5
2 1/7х = 3 9/14 * 1,5
15/7х = 51/14 * 15/10
15/7х = 765/140
х = 765/140 : 15/7
х = 765/140 * 7/15
х = 51/20 = 2,55
2 8/15 1,5
-------- = ----------
3 4/5 z
2 8/15z = 1,5 * 3 4/5
38/15z = 15/10 * 19/5
38/15z = 3/10 * 19/1
38/15z = 57/10
z = 57/10 : 38/15
z = 57/10 * 15/38
z = 57/2 * 3/38
z = 171/76 = 2,25