# Box and Whisker Plot

Related Topics:
More Statistics Lessons

Videos, worksheets, and solutions to help Grade 8 students learn about Box and Whisker Plots.

Box and Whisker Plot is a diagram constructed from a set of numerical data, that shows a box indicating the middle 50% of the ranked statistics, as well as the maximum, minimum and medium statistics.

In these lessons, we will learn how to draw a Box and Whisker Plot from a given set of data and how to read a given Box and Whisker Plot.

### Make a Box-and-Whisker Plot

Box and Whisker Plot
This video will show how to make a ‘Box and Whisker Plot’.

How to make a box-and-whisker plot for a given data set using the following steps?
Step 1: Write the data set in order from least to greatest.
Step 2: Find the second quartile, which is the median for the entire data set.
Step 3: Find the first quartile, which is the median for the lower half of the data set, and find the third quartile, which is the median for the upper half of the data set.
Step 4: Find the least and greatest numbers in the data set. Next, draw a number line with vertical lines at the first, second, and third quartiles, and connect the endpoints of the vertical lines to make a “box”.
Step 5: Plot the least number in the data set and connect it to the box with a segment, and plot the greatest number in the data set and connect it to the box with a segment, to make “whiskers”.

Problem:
The owner of a restaurant wants to find out more about where his patrons are coming from. One day, he decided to gather data about the distance (in miles) that people commuted to get to his restaurant. People reported the following distances travelled:
14, 6, 3, 2, 4, 15, 11, 8, 1, 7, 1, 3, 4, 10, 22, 20

He wants to create a graph that helps him understand the spread of the distances (and the median distance) that people travel. What type of graph should he create?

How To Draw a Box and Whiskers Plot
This video lesson shows how to draw a box and whiskers plot for a set of data.

Problem:
An ecologist surveys the age of about a hundred trees in a local forest. He uses a box and whisker plot to map his data shown below. What is the range of tree ages that he surveyed? What is the median age of a tree in the forest?

Interpreting box and whisker plots
Given a box and whisker plot, learn to analyze data using the quartiles and calculate the percentage of data found within in each quartile.

Try the free Mathway calculator and problem solver below to practice various math topics. Try the given examples, or type in your own problem and check your answer with the step-by-step explanations.