Question

The half-life of a certain radioactive material is 71 hours. An initial amount of the material has a mass of 722 kg. Write an exponential function that models the decay of this material. Find how much radioactive material remains after 17 hours. Round your answer to the nearest thousandth.

Answer 1

Use the radioactive decay formula: A = Ao*2^(-t/h), where

A = 722*2^(-17/71)
find 2^(-17/71) with a calc
A = 722*.847076
A = 611.59 kg after 17 hrs