# The amount of a certain drug present in a patient's body t days after it has been administered is C(t)=5e^-0.2t Determine the average amount of drug present in the patients body for the first 4 days after drug is administered. Help?

The average value of a funtion $f$ over an interval $\left[a , b\right]$ is $\frac{1}{b - a} {\int}_{a}^{b} f \left(x\right) \mathrm{dx}$
Find $\frac{1}{4 - 0} {\int}_{0}^{4} 5 {e}^{- 0.2 t} \mathrm{dt}$