This question refers to the concept of a normal distribution. In a normal distribution:

• About 68% of the data lies within one standard deviation (±1 SD) of the mean.
• 95% of the data lies within two standard deviations (±2 SD) of the mean.
• 99.7% of the data lies within three standard deviations (±3 SD) of the mean.

The shaded region in the image is within ±1 SD from the mean, so 68% of the data falls within this range.

Correct answer: 68%

Would you like more details or have any other questions?

Here are five related questions you might find interesting:

1. How do you calculate standard deviation for a dataset?
2. What does a normal distribution signify in statistics?
3. How is the 68-95-99.7 rule useful in probability?
4. Can the normal distribution be skewed?
5. What are examples of data that follow a normal distribution?

Tip: The "68-95-99.7 rule" is a quick way to remember how data is distributed in a normal distribution.