A radioactive element inside has been decaying for 2 million years? Given that the half-life is 500,000 years,what percent of the parent is currently left?
A)90%
B)50%
C)25%
D)6%

Question

Quizplus · Accepted Answer

After 2 million years, which is equal to 4 half-lives (2,000,000 / 500,000 = 4), the amount of the radioactive element left would be (1/2)^4 = 1/16, which is 6.25%, rounded to 6%.

A Radioactive Element Inside Has Been Decaying for 2 Million