4 целых 3/5 :(1 целая 2/3 - 3 целых 1/5)+1 целая 3/8

         2           1          3

4 3/5 : (1 2/3 - 3 1/5) + 1 3/8 = -1 5/8.

1) 1 2/3 - 3 1/5 = (3 * 1 + 2 / 3) - (5 * 3 + 1 / 5) = 5/3 - 16/5 = (5 * 5 / 3 * 5) - (16 * 3 / 5 * 3) =

= 25/15 - 48/15 = -23/15;

2) 4 3/5 : (- 23/15) = 23/5 * (-15/23) = -3;

3) -3 + 1 3/8 = -3 + 11/8 = -24/8 + 11/8 = - 13/8 = -1 5/8.