cat s-a vandut in prima zi=900x(40/100)=900x(4/10)=90x4=360 kg
cat a ramas dupa prima zi=900-360+260=800 kg
cat s-a vandut a doua zi=800x(30/100)=800x(3/10)=240 kg
cat a ramas dupa a doua zi=800-240=560 kg
cat s-a vandut a treia zi=560x(60/100)+20=560x(6/10)+20=336+20=356 kg
cat a ramas dupa a treia zi=560-356=224 kg