[latex]displaystyle Se~da:\ \ V_1=200ml=0,0002m^3\ \ V_2=50cm^3=0,00005m^3\ \ ho_1=1frac g{cm^3}=1000frac {kg}{m^3}\ \ ho_2=0,9frac g{cm^3}=900frac{kg}{m^3}\ \ ho=?frac {kg}{m^3}\ \ \[/latex] [latex]displaystyle Formule:\ \ ho=frac mV\ \ ho=frac{m_1+m_2}{V_1+V_2}\ \ ho=frac{ ho_1 imes V_1+ ho_2 imes V_2}{V_1+V_2}\ \ \ Calcule:\ \ ho=frac{1000 imes 0,0002+900 imes 0,00005}{0,0002+0,00005}=980frac{kg}{m^3}[/latex]

p=m/V psuc=1g/cm³ palcool=0,9g/cm³ V1=200ml suc=0,2l=0,2dm³= 200cm³ m1/200cm³=1g/cm³→m1 suc=200g m2/50cm³=0,9g/cm³→m2alcool=45g p=(m1+m2)/(V1+V2)= (200g+45g)/(200cm³+50cm³)= 245g/250cm³=49g/50cm³