Melissa H. answered • 05/28/20
I'm here to help!
A box plot shows a number range on number line with a box drawn around the average/middle portion.
A double box plot shows two number ranges on a number line (with boxes drawn around the average/middle portion of each).
A double box plot helps you to quickly compare two sets of data. There are 4 major steps to creating one.
So let's look at your problem. It says that there are two teams who played 15 games, and each time they played they scored points. We are going to be looking at and recording the number of points that each team scored for each game. The problem does not tell us the exact number of points that each team scored - so we get to make up our own, following the rules that the problem gives us. Here are the rules:
There were 15 games
Each team scored 0 or more points each game.
Each team scored 8 or fewer points each game.
The Bulldogs usually scored fewer points than the Warriors.
Using these rules, I have made up some numbers that COULD have been their scores for each game
Game 1. 2. 3. 4. 5. 6. 7. 8. 9. 10. 11. 12. 13. 14. 15
Bulldgs. 7 5 0 3 8 6 5 2 3 5 1 2 4 6 3
Warrs. 8 6 5 8 8 7 8 6 0 4 2 6 5 7 8
Now that we have some numbers to work with, we can create a double box plot by following these steps:
- Find the range of scores for each team
- draw the ranges on your number line
- Find the Median score for each team
- Find the quarter Median scores for each team
- Draw a box around the quarter median scores
- Find the Average score for each team
- Draw a line that represents the average
Step 1: Find the range of scores of each team:
Start by putting the scores in order from least to greatest.
Bulldogs: 0, 1, 2, 2, 3, 3, 3, 4, 5, 5, 5, 6, 6, 7, 8
Warriors: 0, 2, 4, 5, 5, 6, 6, 6, 7, 7, 8, 8, 8, 8, 8
The Bulldogs' scores range from 0-8. The warriors' scores range from 0-8
Now Draw the ranges on your number line like this:
Bulldogs I------------------------------------------I
Warriors I------------------------------------------I
<------------------------------------------------------------------------->
. 0 2 4 6 8 10 12
Step 2. Find the Median score for each team. This is the middle score.
Bulldogs: 0, 1, 2, 2, 3, 3, 3, 4, 5, 5, 5, 6, 6, 7, 8
Warriors: 0, 2, 4, 5, 5, 6, 6, 6, 7, 7, 8, 8, 8, 8, 8
The median (middle) score for the Bulldogs is 4.
The media (middle) score for the Warriors is 6.
Step 3. Find the quarter Median scores for each team. This is the middle number of the sets of numbers to the left and right of the median for each range.
The numbers to the left of the median for the Bulldogs are 0, 1, 2, 2, 3, 3, 3,
The median (middle) number is 2.
The numbers to the right of the median for the Bulldogs are 5, 5, 5, 6, 6, 7, 8
The median (middle) number is 6.
The quarter median numbers for the Bulldogs are 2 and 6.
The numbers to the left of the median for the Warriors are 0, 2, 4, 5, 5, 6, 6,
The median (middle) number is 5.
The numbers to the right of the median for the Warriors are 7, 7, 8, 8, 8, 8, 8
The median (middle) number is 8.
The quarter median numbers for the Warriors are 5 and 8.
Now draw a box that shows the quarter median scores for each team:
Bulldogs I---------[----------------------]---------I
Warriors I---------------------------[---------------]
<------------------------------------------------------------------------->
. 0 2 4 6 8 10 12
Step 4. Find the Average score for each team by adding all of their scores together and dividing by the number of scores.
Bulldogs: 0+1+2+2+3+3+3+4+5+5+5+6+6+7+8= 60
60/15= 4
The Bulldogs' average score was 4
Warriors: 0+2+4+5+5+6+6+6+7+7+8+8+8+8+8=88
88/15= 5.86
The Warriors's average score was 5.86
Now, add a line that represents the average for each team:
Bulldogs I---------[-----------I----------]---------I
Warriors I---------------------------[--I------------]
<------------------------------------------------------------------------->
. 0 2 4 6 8 10 12
That is a finished double box plot that could represent the scores of the two teams over 15 games.
