Understanding Quartiles and Five-Number Summary

This video tutorial explains how to find quartiles and the five-number summary of a data set. It begins with an introduction to the median and quartiles, explaining how they divide data into quarters. The tutorial then covers the five-number summary, which includes the minimum, Q1, median, Q3, and maximum. The locator method for finding quartiles is detailed, with examples provided for both a simple data set and a frequency table. The video concludes with a preview of creating a box plot using the five-number summary.

What is the median of a data set?

• The smallest value in the data set

• The largest value in the data set

• The value in the middle when data is ordered

• The average of all data values

Which quartile represents the median of a data set?

• Q3

• Q2

• Q4

• Q1

What does the five-number summary include?

• Q1, Q2, Q3, Q4, and Q5

• Minimum, maximum, mean, mode, and range

• Minimum, Q1, median, Q3, and maximum

• Mean, median, mode, range, and standard deviation

How do you calculate the locator for Q1 using the locator method?

• 1.00 times the number of data values

• 0.25 times the number of data values

• 0.50 times the number of data values

• 0.75 times the number of data values

If the locator value for Q1 is a decimal, what should you do?

• Ignore the decimal and use the integer part

• Round down to the nearest whole number

• Round up to the nearest whole number

• Use the decimal value as is

In the example with a data set, what is the median value?

• 82

• 18

• 49

• 97

In the example with a data set, what is the value of Q1?

• 6

• 82

• 18

• 49

In the frequency table example, what is the median value?

• 30

• 40

• 50

• 70

In the frequency table example, what is the value of Q3?

• 60

• 50

• 70

• 80

What is the minimum value in the frequency table example?

• 60

• 30

• 40

• 50