640*1/16 = 640:16 = 40
5000*1/100 = 5000:100 = 50
315*4/7 = 315:7*4 = 45*4 = 180
720*9/10 = 720:10*9 = 72*9 = 648
640*1/16 = 640:16 = 40
5000*1/100 = 5000:100 = 50
315*4/7 = 315:7*4 = 45*4 = 180
720*9/10 = 720:10*9 = 72*9 = 648
б=50
в=180
г=648