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cata apa trebuie adaugata la 160 g solutie de concentratie 20 % petru a i se reduce concentratia la jumatate.

Răspuns :

ms1=160
c1=20
md1=20*160/100=32 g
c2=10
ms2=ms1 +mapa
ms2=100*md1/c2=>ms2=100*32/10=320 
ms2-ms1=m apa=>mapa=160