Pre Calculus Question

Question

One particular fast-acting decongestant contains 15mg HCl and you are supposed to take two every dose. It is known that you only need about 4.5mg in your system to be effective, and that the half life is expected to be about 150 minutes. How long before the dose is no longer expected to be active? What would we expect the box to say about taking more? If we were to continue with what the box says for 5 consecutive doses, how much will be in our system right before we would take the 6th dose?

Answer 1

Hi Autumn,

It's an exponential decay of HCl level. Set up an exponential decay equation, solve for the rate constant, and then plug in the various times. Adjust your level as each dose is taken, and let the decay continue ntil the next dose.

You are the 4th person, at least, with this problem set series tonight. You might consider collaborating with your peers? (Alyssa, in particular)

--Cheers, --Mr. d.