Question

In a lab experiment, the decay of a radioactive isotope is being observed. At the beginning of the first day of the experiment the mass of the substance was 1300 grams and mass was decreasing by 14% per day. Determine the mass of the radioactive sample at the beginning of the 11th day of the experiment.

Answer 1

At the beginning of the 11th day, the mass of the radioactive sample was 201.87 grams.

Explanation:

Let's call the mass of the substance after n days "m". We can calculate the mass for each day using the formula:

m = 1300 * (1 - 0.14)^n

Plugging in n = 11:

m = 1300 * (1 - 0.14)^11

m = 1300 * 0.15572634

m = 201.87 grams

So at the beginning of the 11th day, the mass of the radioactive sample was 201.87 grams.