Answer:
[tex]75\ \text{g}[/tex]
Explanation:
t = Time = 180 years
[tex]t_{1/2}[/tex] = Half-life of titanium = 60 years
[tex]N_0[/tex] = Initial amount of titanium = 600 g
We have the relation
[tex]N=N_0e^{-\lambda t}\\\Rightarrow N=N_0e^{-\dfrac{\ln 2}{t_{1/2}}t}\\\Rightarrow N=600e^{-\dfrac{\ln 2}{60}\times 180}\\\Rightarrow N=75\ \text{g}[/tex]
The mass that is left after 180 years is [tex]75\ \text{g}[/tex].
