Answer:
The wood from boat is 17190 years old
Explanation:
For first order radioactive decay-
[tex]\frac{N}{N_{0}}=(\frac{1}{2})^{\frac{t}{t_{0.5}}}[/tex]
where N is remaining amount of radioactive elements after "t" time,[tex]N_{0}[/tex] is initial amount of radioactive element and [tex]t_{0.5}[/tex] is half-life of radioactive element
Here [tex]\frac{N}{N_{0}}[/tex] is 0.125, [tex]t_{0.5}[/tex] is 5730 years
Plug-in all the values in the above equation-
[tex]0.125=(\frac{1}{2})^{\frac{t}{5730}}[/tex]
or, t = 17190
so t is 17190 years or wood from boat is 17190 years old