sorry i'm late. here is the explanation i gave someone else.
Step-by-step explanation:
First, you will need to determine the minimum value, lower quartile, median, upper quartile, and maximum value (Our 5 factors).
(example)
The minimum is 1
The lower quartile is 3
The median is 6
The upper quartile is 9
The maximum value is 12
Now we make a number line.
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0 Â Â Â 1 Â Â Â 2 Â Â Â 3 Â Â Â 4 Â Â Â 5 Â Â Â 6 Â Â Â 7 Â Â Â 8 Â Â Â 9 Â Â Â 10 Â Â Â 11 Â Â Â 12 Â Â Â 13 Â Â Â Â Â Â Â Â Â Â Â Â Â Â Â Â Â Â Â Â Â Â Â
We have our number line finished, so we have to start labeling where are factors are located. I will label them with an "o" above each one.
   o        o            o            o             o
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0 Â Â Â 1 Â Â Â 2 Â Â Â 3 Â Â Â 4 Â Â Â 5 Â Â Â 6 Â Â Â 7 Â Â Â 8 Â Â Â 9 Â Â Â 10 Â Â Â 11 Â Â Â 12 Â Â Â 13 Â Â
 So, we got it all set. so now, we finish it off. We make a box, starting from the lower quartile and ending at the upper quartile like this. ( I could not make the full box, so I made a line above it.)
           ||
   o        o            o            o             o
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0 Â Â Â 1 Â Â Â 2 Â Â Â 3 Â Â Â 4 Â Â Â 5 Â Â Â 6 Â Â Â 7 Â Â Â 8 Â Â Â 9 Â Â Â 10 Â Â Â 11 Â Â Â 12 Â Â Â 13 Â Â Â
Then, we make a whisker from the minimum to the lower quartile, then the upper quartile to the maximum like shown.
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   o        o            o            o             o
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0 Â Â Â 1 Â Â Â 2 Â Â Â 3 Â Â Â 4 Â Â Â 5 Â Â Â 6 Â Â Â 7 Â Â Â 8 Â Â Â 9 Â Â Â 10 Â Â Â 11 Â Â Â 12 Â Â Â 13 Â Â Â
Then finally divide the box by the median.
 Â
    ||
                        |   Â
   o        o            o            o             o
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0 Â Â Â 1 Â Â Â 2 Â Â Â 3 Â Â Â 4 Â Â Â 5 Â Â Â 6 Â Â Â 7 Â Â Â 8 Â Â Â 9 Â Â Â 10 Â Â Â 11 Â Â Â 12 Â Â Â 13 Â
                                      ^
                                      |
                                      |
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Your final product should look like the one above, except the fact that the box is NOT a line.
have a good day