Răspuns:
39.
x+y=100 kg
x-38=y+38 =>x-y=76 =>x=y+76
y+76+y=100 ; 2y=24
=>y=12 kg =>x=88 kg
40.
x+y=4300 kg
x=y+186
y+186+y=4300 ; 2y=4114
=>y=2057 kg =>x=2243 kg
41.
888:2=444 kg pentru cantină
x-gradinita
y-scoala
x+y=444 kg
x=y-216
y-216+y=444 ; 2y=660
=>y=330 kg =>x=114 kg