A comprehensive guide to understanding standard deviation in normal distribution problems and probability calculations.
• The normal distribution is a symmetrical probability distribution where the mean, mode, and median are equal, characterized by its bell-shaped curve.
• Key probability ranges in a normal distribution include:
- 68% of data falls within one standard deviation of the mean
- 95% of data falls within two standard deviations
- 99.7% of data falls within three standard deviations
• The guide covers essential concepts including calculating variance in normal distribution examples, standardization, and hypothesis testing.
• Practical applications are demonstrated through various examples involving measurements, weights, and statistical analysis.