Quartiles and Interquartile Range

Front

What is a quartile?

Back

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

Front

What does the upper quartile (Q3) represent?

Back

The upper quartile (Q3) represents the value below which 75% of the data falls.

Front

What does the lower quartile (Q1) represent?

Back

The lower quartile (Q1) represents the value below which 25% of the data falls.

Front

How do you calculate the interquartile range (IQR)?

Back

The interquartile range (IQR) is calculated by subtracting the lower quartile (Q1) from the upper quartile (Q3): IQR = Q3 - Q1.

Front

What is the median of a data set?

Back

The median is the middle value of a data set when it is ordered from least to greatest.

Front

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

Back

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

Front

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

Back

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

Front

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

Back

IQR = Q3 - Q1 = 53 - 20 = 33.

Front

What does it mean if a data set has a large interquartile range (IQR)?

Back

A large IQR indicates that there is a wide spread of the middle 50% of the data.

Front

What is the first step in finding quartiles?

Back

The first step is to order the data set from least to greatest.