Interquartile Range
Aligned To Common Core Standard:
Grade 6 Statistics  .SP.B.5C
What Is Interquartile Range? When analyzing data through a graph, there are a variety of different quantities that can provide an insight into the trends in the data. A graph is divided into four equal parts, each of which is known as a quarter. Q1 is the part that represents the middle value of the first half of the data. It is onequarter of the whole data. You can also refer to it as 25% of the entire data set. Q2 is the median of the entire data. The value that lies exactly at onehalf of the data. You can also refer to it as 50% of the whole data set. Q3 is the middle value of the second half of the data. It is threefourth of the data, and you can refer to it as 75% of the entire data. The interquartile range is the measurement of where the middle fifty of the data lies. It is calculated by subtracted onefourth value of the data, Q1, from the threefourth value of the data, Q3. Interquartile range (IQR)=Q3Q1 To calculate IQR, you have to find out Q1 and Q3. Q1=1/4×total frequency The value corresponding to this value is the Q1 of the data. Q3=3/4×total frequency The value corresponding to this value is the Q3 of the data. You subtract Q1 from Q3, and you get IQR!
Printable Worksheets, Quizzes, And the Lessons
 Determining Interquartile
Ranges Lesson We go over the basic sorting system used at this
grade level.
 Interquartile Range  Practice
Worksheet 1  We highlight harder problems in version 4.
 IQR Worksheet 2  Calculate the median, quarter one, quater three, and the interquartile range.
 IQR Worksheet 3  Another go around with it.
 IQR Worksheet 4 These are helpful to make sense of the process for solving these types of problems.
 Story Based Interquartile Ranges Worksheet 1  In these we give the problem purpose by giving you some context for the data.
 Story Based IQR Worksheet 2  Susan weighed all of her pets to determine the following information. The weights
in pounds were as follows {22,100,1,12,25,13}.

Story Based IQR Worksheet 3  Jordan went fishing and recorded the weights of each fish that he and his friend Cole
caught. Jordan: {24,10,16,38,16,42}. Cole: {4,10,12,8,5,11}

Story Based IQR Worksheet 4  Ann had a party and invited guests from all around. She decided to record the miles
traveled by each attendee.

Interquartile Range Quiz 1  The quizzes follow a unique format.
 Interquartile Range Quiz 2  The number of students riding the activity bus varied each Friday. Here are the totals from week to week.