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Stupid Box Plot Maths Question

When comparing Box Plots:

I know what it means if the IQR is bigger (the content is less consistent), but what does it mean if the Range is bigger. My book says that they mean the same thing, but sometimes the IQR and Range differ (e.g one box having a higher IQR, while having a lower R)

Please help, I can't find this online, it's so dumb it's making me angry.
Reply 1
Original post by solar222222
When comparing Box Plots:

I know what it means if the IQR is bigger (the content is less consistent), but what does it mean if the Range is bigger. My book says that they mean the same thing, but sometimes the IQR and Range differ (e.g one box having a higher IQR, while having a lower R)

Please help, I can't find this online, it's so dumb it's making me angry.


The Lowest Value = Lowest data shown
The Highest Value = Highest Data Shown
The Range = The amount between the lowest value and the highest value.
Upper Quartile = 75% of the range + Lower Value
Lower Quartile = 25% of the range + Lower Value
Interquartile Range = The amount between the Lower Quartile and the Upper Quartile
Median = 50% of the range + Lowest Value


Hopefully this makes sense ! It's hard to describe it without the example! Could you post the example on here?
Hopefully this makes sense ! It's hard to describe it without the example! Could you post the example on here?

Of course.

Say we have 2 Box Plots, one that shows the information about the weight guessed by the boys, and the other represents the girls. Compare the two:

- Girls have a larger median, so the guessed heavier weights.
- Girls have a smaller IQR, so there is less variation in their guesses.
- Girls have a bigger range....What do I say here?
Reply 3
Original post by solar222222
Hopefully this makes sense ! It's hard to describe it without the example! Could you post the example on here?


Of course.

Say we have 2 Box Plots, one that shows the information about the weight guessed by the boys, and the other represents the girls. Compare the two:

- Girls have a larger median, so the guessed heavier weights.
- Girls have a smaller IQR, so there is less variation in their guesses.
- Girls have a bigger range....What do I say here?

If there is a bigger median, it means that girls are heavier on average.

If there is a smaller IQR, it means that the girls weights tend to be the same so yes, less variation and difference in weight.

If there is a bigger range, it means that there is more variety in girls weights than in boys weights.

Hope this helps!? :smile::smile:
So they have both less and more variation? That makes no sense.I'm sorry, I'm still confused and it's driving me crazy.My book is treating it as if every time the IQR and Range are always the same (as in they both bigger or small than the other box plot). But I've had cases where they've been different and it's cost me the exam
Original post by solar222222


So they have both less and more variation? That makes no sense.I'm sorry, I'm still confused and it's driving me crazy.

My book is treating it as if every time the IQR and Range are always the same (as in they both bigger or small than the other box plot). But I've had cases where they've been different and it's cost me the exam........
Original post by solar222222
When comparing Box Plots:

I know what it means if the IQR is bigger (the content is less consistent), but what does it mean if the Range is bigger. My book says that they mean the same thing, but sometimes the IQR and Range differ (e.g one box having a higher IQR, while having a lower R)

Please help, I can't find this online, it's so dumb it's making me angry.


If you done the maths paper recently no point doing that **** now lmao aint coming again
Original post by junayd1998
If you done the maths paper recently no point doing that **** now lmao aint coming again


Oh, is that how it works, do they not repeat? Well that sucks.
Original post by solar222222
Oh, is that how it works, do they not repeat? Well that sucks.


It wont come trust me loool revise histograms, cumtalive frequency and frequency poloygons.
Original post by junayd1998
It wont come trust me loool revise histograms, cumtalive frequency and frequency poloygons.


Thank you! =D

Anything else? They probably won't make us use compasses again, can't really remember much else (and I also only got to question 17, I didn't do so good)
Original post by solar222222
Thank you! =D

Anything else? They probably won't make us use compasses again, can't really remember much else (and I also only got to question 17, I didn't do so good)


Your welcome here is a full calc topic list https://www.mathswatchvle.com/docs/PredictionsforEdexcel2016.pdf

I think i scraped 70 marks barely

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