Example Card: Displaying Data in a Box-and-Whisker Plot
Apply displaying data in a box-and-whisker plot in Grade 9 math — Let's turn a list of video game scores into a clear visual summary. Part of Polynomials and Factoring for Grade 9.
Key Concepts
Let's turn a list of video game scores into a clear visual summary. This is a great example of the first key idea, displaying data in a box and whisker plot.
Example Problem Make a box and whisker plot for these game scores: $150, 220, 180, 300, 250, 400, 450, 500, 260, 210, 190, 520, 160, 230, 280$. Half the scores fall between which two values?
Step by Step 1. First, order the data from least to greatest. $$ (150, 160, 180, 190, 210, 220, 230, 250, 260, 280, 300, 400, 450, 500, 520) $$ 2. Find the minimum, maximum, median, and quartiles. Minimum: $150$ Maximum: $520$ Median (the 8th value): $250$ First Quartile ($Q 1$, median of the lower half): $190$ Third Quartile ($Q 3$, median of the upper half): $400$ 3. Draw a number line. Then, draw a box from $Q 1$ ($190$) to $Q 3$ ($400$), add a vertical line inside the box at the median ($250$), and draw whiskers from the box to the minimum ($150$) and maximum ($520$). 4. The box represents the middle half of the data. Therefore, half of the game scores are between $190$ and $400$.
Common Questions
What is 'Displaying Data in a Box-and-Whisker Plot' in Grade 9 math?
Let's turn a list of video game scores into a clear visual summary. This is a great example of the first key idea, displaying data in a box-and-whisker plot.
How do you solve problems involving 'Displaying Data in a Box-and-Whisker Plot'?
This is a great example of the first key idea, displaying data in a box-and-whisker plot. Half the scores fall between which two values?.
Why is 'Displaying Data in a Box-and-Whisker Plot' an important Grade 9 math skill?
Common mistake tip: A very common mistake is forgetting to order the data from smallest to largest before doing anything else.. If you calculate the median or quartiles from an unordered list, your answer will almost always be wrong.