50*(х : 16)=40.150
х : 16 = 40.150 : 50
х : 16 = 803
х = 803*16
х = 12.848
_____________________________
2.700 + у*400 = 170.700 (170.700-2.700=168.000)
y*400 = 168.000
у = 168.000 : 400
у = 420
______________________________
(12.300-30) : k = 30
12.270 : к = 30
к = 12.270 : 30
к = 409