(3/15-две целых 7/25): 1целую 2/25+1целая 4/13

(3/15 - 2 7/25) : 1 2/25 + 1 4/13 = (3/15 - 57/25) : 27/25 + 17/13 = (15/75 - 171/75):27/25 + 17/13 = -156/75 * 25/27 + 17/13 = - 52/27 + 17/13 = -676/351 + 221/351 = -455/351 = -35/27 = - 1 8/27