Question

How long will it take a sample of radioactive substance to decay to half of its original amount, if it decays according to function A(t)=750e^ -.119t, where t is the time in years? Round your answer to the nearest hundredth year.

T equals time???? I don't see the time anywhere! Can someone please help me figure this mess out?

Answer 1

This is the formula to find the amt. A of that radioactive substance after time t.


`A_t=750e^(0.119t)`

We want to find out low long it will take for A to become half of its original amount.
We don't know the original amount, and the substance is not decaying at a constant rate (but rather an exponential one) so we can't answer that question.

Is there any information you forgot to give? Double check yourself.