A certain radioactive isotope has leaked into a small stream. Three hundred days after the leak, 3% of the original amount of the substance remained. Determine the half-life of this radioactive isotope.

If the half-life is t, then every t days, the amount of the radioactive isotope will be cut in half.

(1/2) ^ (number of half-lives) = 3%

number of half-lives = ln (0.03) / ln (0.5)

This gives the number of half-lives as 5.06.

Then 300 days = (5.06) (length of 1 half-life)

length of 1 half-life = 300 / 5.06 = 59.29 days