Drug concentration

Question

The concentration C(t) of a certain drug in the bloodstream after (t) minutes is given by the formula C(t)=(0.03 - e^-0.2t) what is the concentration after 9 minutes? Round to the three decimal places.

Answer 1

You just need to plug in t = 9 into the equation C(t) = 0.03 - e^-0.2t but I suspect the equation probably should be C(t) = (0.03)e^-0.2t otherwise it's not going to give a reasonable answer and that exponential equation is typical for drug concentration calculations.

Assuming the equation is C(t) = (0.03)e^-0.2t then the concentration after 9 minutes would be

C(9) = (0.03)e^-0.2(9) = (0.03)e^-1.8 = (0.03)(0.1653) = 0.004959 and rounding to 3 decimal places gives 0.005