1. 15 * 1/15 - (6 * 1/5 + 5 * 8/11)
15 * 1/15 = 1
6 * 1/5 = 6/5
5 * 8/11 = 40/11
6/5 + 40/11 = (66 + 200) / 55 = 266/55
1 - 266/55 = - 211/55 = - 3 46/55
2. 5 * 3/17 - (6 * 4/7 - 9 * 14/17)
5 * 3/17 = 15/17
6 * 4/7 = 24/7
9 * 14/17 = 126/17
24/7 - 126/17 = (408-882)/119 = - 474/119
15/17 - (-474/119) = 15/17 + 474/119 = (105+474) / 119 = 579/119 = 4 103/119