(13 93/98-15 17/49) -(13 93/98-2 5/7) = ?

1) 13 93/98 - 15 17/49

Общий знаменатель 98

13 93/98 - 15 17*2/98 =  (13-15)+ (93/98 - 34/98)=-2+ 59/98=
=-196/98+59/98=-137/98=-1 39/98

2) 13 93/98-2 5/7= (13-2)+(93/98- 5*14/98)= 11+ 23/98=11 23/98

3)-1 39/98 + 11 23/98=
=-1 39/98 + 10 121/98 = 9 82/98