140:20 500+(600-3•100):10 9000:(100-90):9•2 560:7 8100:900 3200:800

Question

140:20 500+(600-3•100):10
9000:(100-90):9•2
560:7
8100:900
3200:800

Answer 1

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=900:9*2=100*2=200, 560:7=80, 8100:900=9, 3200:800=4