Question

Select the correct answer.Which of the following situations can be modeled by the equation?A radioactive decay of 6.67% per year for a block of plutonium-238 that has an initial mass of 7.71 grams. B. A radioactive decay of 93.33% per year for a block of plutonium-238 that has an initial mass of 7.71 grams. C. A radioactive decay of 92.29% per year for a block of plutonium-238 that has an initial mass of 93.33 grams. D. A radioactive decay of 7.71% per year for a block of plutonium-238 that has an initial mass of 93.33 grams.

Answer 1

In the given expression, the decaying factor is (0.9333)^t:

`m=7.71(0.9333)^t`

Due to that factor, for each unit t increases, the expression is reduced to 0.9333 of the previous value. The relative difference between the previous value and the next one, is:

`1-0.9333=0.0667=6.67\%`

Then, this equation models a decay of 6.67% per unit t. It could be a radioactive decay rate where the time is measured in years.

Therefore, the correct choice is: Option A) A radioactive decay of 6.67% per year.