BOX AND WHISKER PLOT
Definition Of Box And Whisker Plot
A Box-and-Whisker Plot shows the distribution of a set of data along a number line, dividing the data into four parts using the median and quartiles.
Examples of Box and Whisker Plot
A sample of box-and-whisker plot is shown below
Video Examples: Box and Whisker Plot
Solved Example on Box and Whisker Plot
Ques: The box-and-whisker plot below shows the amount of calories in some bakery items. Use it to find the difference between the upper and lower quartiles.
Choices:
A. 150
B. 650
C. 500
D. 250
Correct Answer: A
Solution:
Step 1: From the box-and-whisker plot shown, we learn that the upper quartile value is 650 and the lower quartile value is 500.
Step 2: So, the difference between the two values is 650 - 500 = 150.
Real world Connections for Box and Whisker Plot
Box-and-whisker plots are useful in comparing data.
For example, the prices of different commodities, weights of students in a class, your test scores, etc can be compared using box-and-whisker plots.
Quick Summary
- Visual representation of data distribution.
- Shows median, quartiles, and outliers.
- Useful for comparing different datasets.
🍎 Teacher Insights
Emphasize the connection between quartiles and percentages. Use real-world examples to illustrate the usefulness of box plots in comparing data sets, such as test scores or commodity prices. Discuss the impact of outliers on the plot.🎓 Prerequisites
- Basic arithmetic
- Understanding of median
- Concept of quartiles
Check Your Knowledge
Q1: What does the median represent in a box and whisker plot?
Q2: The interquartile range (IQR) is:
Frequently Asked Questions
Q: What does the box represent?
A: The box represents the interquartile range (IQR), which contains the middle 50% of the data.
Q: What do the whiskers represent?
A: The whiskers typically extend to the farthest data point within 1.5 times the IQR from the quartiles. Points beyond this are considered outliers.
Q: What is an outlier?
A: An outlier is a data point that is significantly different from other data points in the set. On a box plot, they are typically marked as individual points beyond the whiskers.