1) (3 5/6+5/12)×1 5/51

Расставим действия:

          1           2  

(3 5/6 + 5/12) * 1 5/51 = 51/12 * 1 5/51 = 51/12 * 56/51 = 56/12 = 14/3 = 4 2/3.

1) 3 5/6 + 5/12 = (3 * 6 + 5 / 6) + 5/12 = 23/6 + 5/12 = 23 * 2 / 6 * 2 + 5/12 = 46/12 + 5/12 =

=51/12;

2) 51/12 * 1 5/51 = 51/12 * 56/51 = 56/12 = 14/3 = 4 2/3.