Question

An element with mass 570 grams decays by 18% per minute. How much of the element is remaining after 13 minutes, to the nearest 10th of a gram?

Answer 1

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Answer:

43.2 grams

Explanation:

The exponential equation for the decay can be written as ...

amount remaining = (initial amount)(1 -decay rate)^t

= 570(1 -0.18)^t

We want to find the amount remaining after 13 minutes. Evaluating this equation for t=13, we have ...

amount remaining = 570(0.82^13) ≈ 43.2 . . . grams