Write an expoential function showing the relationship between y and t.

Question

There was a sample of 750 milligrams of radioactive substance to start a study.Since then, the sample has decayed by 1.2% each year.Let t be the number of years since the start of the study. Let y be the mass of the sample in milligrams. Write an exponential function showing the relationship between y and t.

Answer 1

y = A₀e^-kt, where y is the amount remaining at time t, A₀ is the initial amount, and k is the decay rate expressed as a decimal.  

 

So, y = 750e^-0.012t