72/80 - (15/80 - 12/80) = 69/80
27/50+3/50-7/50=27/50-4/50=23/50
116/125 - 24/125 - 41/125 = 51/125
31/40+6/40-16/40-4/40=15/40+2/40=17/40
72/80 - (15/80 - 12/80) = 69/80
27/50+3/50-7/50=27/50-4/50=23/50
116/125 - 24/125 - 41/125 = 51/125
31/40+6/40-16/40-4/40=15/40+2/40=17/40