Assume that 500,000 people take the GED exam (high school proficiency exam) each year and their scores form a normal distribution. If Danny scores two standard deviations below the mean, what percentile is he?

Step 1 ：Assume that 500,000 people take the GED exam each year and their scores form a normal distribution. If Danny scores two standard deviations below the mean, we need to find the corresponding percentile.

Step 2 ：Since Danny's score is two standard deviations below the mean, we can use the z-score table or a calculator to find the corresponding percentile. The z-score is -2.

Step 3 ：Using the z-score table or a calculator, we find that the percentile corresponding to a z-score of -2 is approximately 2.28.

Step 4 ：\(\boxed{\text{Final Answer: Danny is in the 2.28th percentile.}}\)