Ex 42 am nevoie de ajutor urgent

80x50=4000 =78x45 20x20=400 =23x15
40x90=3600 =35x94 30x10=300=25x11
50x20=1000= 54x20 10x20=200=13x17
60x100=6000=62x99 50x40=2000=48x37