Question

HELP PLEASE!!?!
5. The half-life of a certain radioactive material is 78 hours. An initial amount of the material has a mass of 790 kg. Write an exponential function that models the decay of this material. Find how much radioactive material remains after 18 hours. Round your answer to the nearest thousandth.

Answer 1

I belive you need the equation A(t) = A0*(1/2)^(t/h) where A(t) is the amount you have after t time has passed. A0 is the initial amount, t is the time that has passed and h is the half life. So in you case h = 78 hours, A(0)= 790kg, t = 18hours.