Front

What is the mean in a normal distribution?

Back

The mean is the average value of a dataset, 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 the Empirical Rule state about normal distributions?

Back

The Empirical Rule states that approximately 68% of data falls within one standard deviation of the mean, 95% within two standard deviations, and 99.7% within three standard deviations.

Front

If the mean life of a tire is 30,000 km and the standard deviation is 2000 km, what is the range for 68% of tires?

Back

28,000 km to 32,000 km.

Front

What does a normal distribution curve look like?

Back

A normal distribution curve is bell-shaped, symmetric about the mean, with most of the data clustering around the mean.

Front

What is variance in a normal distribution?

Back

Variance is the square of the standard deviation and measures how far a set of numbers is spread out from their average value.

Front

How do you find the z-score in a normal distribution?

Back

The z-score is calculated by subtracting the mean from the value and then dividing by the standard deviation.

Front

What percentage of data falls between the mean and one standard deviation above the mean in a normal distribution?

Back

Approximately 34% of the data falls between the mean and one standard deviation above the mean.

Front

What is the significance of the 1st quartile in a normal distribution?

Back

The 1st quartile (Q1) is the value below which 25% of the data falls.

Front

What does it mean if a data point is one standard deviation above the mean?

Back

It indicates that the data point is higher than the average value by an amount equal to the standard deviation.