不正確；
?$m_{水}=ρ_{水}V_{水}=1\ \mathrm {g/cm}^3×50\ \mathrm {cm}^3=50\ \mathrm {g}$?
?$m_{鹽水}=m_{水}+m_{鹽}=50\ \mathrm {g}+22\ \mathrm {g}=72\ \mathrm {g}$?
?$ρ_{鹽水}=\frac {m_{鹽水} }{V_{鹽水}}=\frac {72\ \mathrm {g}}{60\ \mathrm {cm}^3}=1.2\ \mathrm {g/cm}^3$?
