Standard 11 Checkpoint

Front

What is the mean in a normal distribution?

Back

The mean is the average value of a set of data points, representing the center of the distribution.

Front

What is the standard deviation in a normal distribution?

Back

The standard deviation measures the amount of variation or dispersion in a set of values.

Front

What does it mean if a distribution is normally distributed?

Back

A normally distributed dataset has a symmetric bell-shaped curve where most of the observations cluster around the central peak.

Front

How do you find the percentage of data within one standard deviation of the mean in a normal distribution?

Back

Approximately 68% of the data falls within one standard deviation of the mean.

Front

What is the empirical rule in statistics?

Back

The empirical rule states that for a normal distribution: 68% of data falls within 1 standard deviation, 95% within 2, and 99.7% within 3 standard deviations.

Front

How do you calculate a z-score?

Back

Z-score = (X - μ) / σ, where X is the value, μ is the mean, and σ is the standard deviation.

Front

What is a z-table used for?

Back

A z-table shows the percentage of values to the left of a given z-score in a standard normal distribution.

Front

What is the significance of the 90th percentile in a normal distribution?

Back

The 90th percentile is the value below which 90% of the data falls.

Front

How do you interpret a z-score of 1.5?

Back

A z-score of 1.5 indicates that the value is 1.5 standard deviations above the mean.

Front

What is the formula for finding the area under the normal curve?

Back

The area under the normal curve can be found using integration or z-scores and a z-table.