Question

The half-life of a radioactive kind of barium is 3 minutes. If you start with 96 grams of it, how much will be left after 9 minutes?

Answer 1

We will have the following:

We will determine the decrease after 9 minutes as follows:

`96((1)/(2))^3=12`

Here each unit in the exponent represent each half life period.

So, after 9 minutes (3 sets of the half life) there wil be 12 grams of it.