Quartiles and Interquartile Range

If the lower quartile (Q1) is 20 and the upper quartile (Q3) is 53, what is the interquartile range (IQR)?

• 25

• 30

• 33

• 40

What does the lower quartile (Q1) represent?

• The value below which 25% of the data falls.

• The median of the data set.

• The highest value in the data set.

• The average of the data set.

What does the upper quartile (Q3) represent?

• The value below which 50% of the data falls.

• The value below which 75% of the data falls.

• The value below which 25% of the data falls.

• The average value of the data set.

If a data set has the values: 10, 20, 30, 40, 50, what is the median?

• 20

• 30

• 40

• 25

What is the significance of the median in a data set?

• It provides a measure of central tendency that is not affected by extreme values (outliers).

• It is the average of all data points in the set.

• It represents the most frequently occurring value in the data set.

• It is always equal to the mean of the data set.

True or False: The median is always one of the values in the data set.

• True, the median is always one of the values in the data set.

• False, the median may not be one of the actual data values, especially if the number of data points is even.

• True, the median is the average of the two middle values in an even data set.

• False, the median is always the highest value in the data set.

Why is it important to understand quartiles and IQR in statistics?

• It helps in analyzing data distribution and identifying outliers.

• It is only useful for calculating averages.

• It is primarily used for graphical representation of data.

• It has no significant impact on data analysis.

What is the range of a data set?

• The average of all values in the data set.

• The difference between the highest and lowest values in the data set.

• The sum of all values in the data set divided by the number of values.

• The value that appears most frequently in the data set.

What is a quartile?

• A type of quantile that divides a data set into four equal parts, each containing 25% of the data.

• A statistical measure that indicates the average of a data set.

• A method for calculating the median of a data set.

• A graphical representation of data distribution.

What is the purpose of finding quartiles in a data set?

• Quartiles help to understand the distribution of data by identifying the spread and center of the data.

• Quartiles are used to calculate the mean of the data set.

• Quartiles are primarily used to find the mode of the data set.

• Quartiles help to eliminate outliers from the data set.