Question

A radioactive substance decays at a rate of 3.4% per day. If it starts at 200 grams, how

many days will it take for the substance to decay to less than 150 grams?

Answer 1

Answer: 9

Explanation:

Since the percent is decaying, you subtract 3.4 from 100, which gets you 96.6

200(0.966)^9 gets you 146.5 which is less than 150