The anti-inflammation drug Advil has a half-life of 2 hours. That is, the amount of the drug present

The anti-inflammation drug Advil has a half-life of 2 hours. That is, the amount of the drug present in the body is halved every two hours. What fraction of the initial amount of the drug will be left in the body after 4 hours?

• At time 0, we have 100%
• At time 2, we have 100% * 1/2 = 50% or 1/2
• At time 4, we have 1/2 * 1/2 = 1/4