(Solved): Suppose a sample of a certain substance decayed to 67.2% of its original amount after 300 days. Let ...

Suppose a sample of a certain substance decayed to 67.2% of its original amount after 300 days. Let y(t) - Aekt be the mass remaining after t days. What is the half-life (in days) of this substance? Write a number. (Round your answer to two decimal places.)