140:20 = 7500 + (600 - 3 100):10 = 500 + (600 - 300):10 = 500 + 300:10 = 500 + 30 = 5309000:(100-90):9 2 = 9000:(10):9 2 = 9000:10 2 = 900 * 2 = 1800560:7 = 808100:900 = 93200:800 = 4
Therefore, the final expression is: 7 530 1800 80 9 4
140:20 = 7
500 + (600 - 3 100):10 = 500 + (600 - 300):10 = 500 + 300:10 = 500 + 30 = 530
9000:(100-90):9 2 = 9000:(10):9 2 = 9000:10 2 = 900 * 2 = 1800
560:7 = 80
8100:900 = 9
3200:800 = 4
Therefore, the final expression is: 7 530 1800 80 9 4