Find the present value of the future value.
-The decay of 291 mg of an isotope is given by A(t)= 291e-0.022t, where t is time in years since the initial amount of 291 mg was present. Find the amount (to the nearest milligram) left after 38 years.
A) 126
B) 63
C) 285
D) 123

Question

Quizplus · Accepted Answer

The amount left after 38 years is calculated using the given decay formula A(t) = 291e^(-0.022t). Substituting t = 38, we get A(38) = 291e^(-0.022*38). Calculating this gives approximately 126 mg (to the nearest milligram).

Find the Present Value of the Future Value