1. 1) 40:72 = 40/72 = 5/9
2) 5/9 - 1/3 = 5/9 - 3/9 = 2/9
3) 2/9 * 9/4 = 1/2
4) 1/2 +8/9 = 9/18 + 16/18 = 25/18 = 1 7/18
2. 1) 30 : 27 = 30/27 = 10/9
2) 10/9 - 1/3 = 10/9 - 3/9 = 7/9
3) 7/9 * 15/7 = 15/9
4) 15/9 + 2/5 = 75/45 + 18/45 = 93/45 = 93/45 = 2 3/45