c=md×100/ms<=> 40=md×100/200=>md=40×2=> md=80g
c= md×100/ms<=> 20=md×100/300=>md=20×3=> md=60g
mdf=80+60=140g; msf=200+300=500g
cf=140×100/500=>cf=140/5=28=>cf=28%
40>28>20 concentratia din solutia 1 s-a diluat cu concentratia din solutia 2
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