Question

An initial sample of 555 g of a radioactive substance decays according to the function

where A(t)=555e^-0.029t
where t is given in years.
(a) How many grams of the substance will remain after 28 years? Round your answer to one decimal place.

Answer=246.40292776
(b) What is the half-life of the substance? Round your answer to one decimal place.

I Dont know how to solve (b) can anyone help me

Answer 1

Answer: 23.9

Explanation:

It's asking: after how many years will there be half of the sample remaining?

555e^-0.029t=555/2

Solving this gives you 23.9