1 5/7- 4 3/13:1 19/26= 12/7- 55/13:45/26= 12/7- 55/13* 26/45= 12/7 - 11*2/9= 12/7 - 22/9= 108/63 - 154/63= -46/63
1 5/7- 4 3/13:1 19/26= 12/7- 55/13:45/26= 12/7- 55/13* 26/45= 12/7 - 11*2/9= 12/7 - 22/9= 108/63 - 154/63= -46/63