1.
3 1/9 : 2 1/3 - 2 5/6
= 28/9 : 7/3 - 17/6 =
= 28/9 * 3/7 - 17/6 = 4/3 - 17/6 =
= 8/6 - 17/6 = - 9/6 = - 3/2 = - 1 1/2,
или:
1) 3 1/9 : 2 1/3 = 28/9 : 7/3 = 28/9 * 3/7 = 4/3 = 1 1/3,
2) 1 1/3 - 2 5/6 = 4/3 - 17/6 = 8/6 - 17/6 = - 9/6 = - 3/2 = - 1 1/2,
2.
1 5/7 - 4 3/13 : 1 19/26 = 12/7 - 55/13 : 45/26 =
= 12/7 - 55/13 * 26/45 = 12/7 - 22/9 =
= 108/63 - 154/63 = - 46/63,
или:
1) 4 3/13 : 1 19/26 = 55/13 : 45/26 = 55/13 * 26/45 = 22/9 = 2 4/9,
2) 1 5/7 - 2 4/9 = 12/7 - 22/9 = 108/63 - 154/63 = - 46/63