The amount A, in milligrams, of a 10milligram dose of a drug remaining in the body after T hours is given by the formula A=10(0.8)^T. Find, to the nearest tent of an hour, how long it takes for half the drug dose to leave the body
A=10(0.8)^T
5=10(0.8)^T
1/2=0.8^T
T=log(1/2) / log(.8)
T=3.106 hours.
