• Mean: The average of a set of numbers calculated by adding them together and dividing by the count of numbers.

• Median: The middle value in a set of numbers when arranged in order.

• Mode: The number that appears most frequently in a set of number

Measures of Variability are statistics that describe the spread or dispersion of a set of data points. Common measures include range, variance, standard deviation, and interquartile range.

Difference of Ungrouped and Grouped Data

Ungrouped Data:

• Data points are individual values.

• Variability measures like range, variance, and standard deviation are calculated directly from the data points.

Grouped Data:

• Data is grouped into intervals or classes.

• Variability measures are calculated using class midpoints or frequencies within each class.