Answer:
About 12.5%
Explanation:
Every half life usually eliminates about half or 50% of drugs that is stored in the body system.
Therefore, after one half life, the percentage of drug stored in the body will be 50%, after two half lives it will be reduced by 50% which is 25%.
After three half lives, the percentage of drug stored in the body will also be eliminated by 50% which will be half of 25% and it will be 12.5%.
Therefore, the answer is 12.5%.