2 11/15*1 1/19-1 1/9*3/10-1 1/6*1 1/6

Расставим действия:

1 4 2 5 3

2 11/15 * 1 1/19 - 1 1/9 * 3/10 - 1 1/6 * 1 1/6 = 809/684.

1) 2 11/15 * 1 1/19 = 41/15 * 20/19 = 820/285 = 164/57;

2) 1 1/9 * 3/10 = 10/9 * 3/10 = 30/90 = 1/3;

3) 1 1/6 * 1 1/6 = 7/6 * 7/6 = 49/36;

4) 164/57 - 1/3 = 164/57 - 19/57 = 145/57;

5) 145/57 - 49/36 = 1740/684 - 931/684 = 809/684.