Practice on Interquartile Range

Front

What is the interquartile range (IQR)?

Back

The interquartile range (IQR) is the difference between the upper quartile (Q3) and the lower quartile (Q1) in a data set.

Front

How do you calculate the IQR?

Back

IQR = Q3 - Q1.

Front

What does Q1 represent in a data set?

Back

Q1, or the first quartile, represents the value below which 25% of the data falls.

Front

What does Q3 represent in a data set?

Back

Q3, or the third quartile, represents the value below which 75% of the data falls.

Front

If Q1 is 3.5 and Q3 is 10.5, what is the IQR?

Back

IQR = 10.5 - 3.5 = 7.

Front

True or False: The IQR can be negative.

Back

False. The IQR is always a non-negative value.

Front

What is the purpose of calculating the IQR?

Back

The IQR is used to measure the spread of the middle 50% of a data set and to identify outliers.

Front

Given the five-number summary: Minimum: 2, Q1: 3.5, Median: 6, Q3: 10.5, Maximum: 12, what is the IQR?

Back

IQR = 10.5 - 3.5 = 7.

Front

Find the IQR for the following data: 50, 60, 82, 86, 94, 110.

Back

IQR = Q3 - Q1 = 86 - 60 = 26.

Front

What is an outlier in a data set?

Back

An outlier is a data point that is significantly different from the other data points in the set.