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    Hi!
    You no histograms in maths. Well I was just wondering wot u wud use them 2 show?????? PLEASE PLEASE PLEASE help, I really need 2 no!!!
    THANX!
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    (Original post by CHAD)
    Hi!
    You no histograms in maths. Well I was just wondering wot u wud use them 2 show?????? PLEASE PLEASE PLEASE help, I really need 2 no!!!
    THANX!
    the um size of various groups of seperate data.
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    (Original post by ]{ingnik)
    the um size of various groups of seperate data.
    anything relating to frequency

    how many people could do a task in 1minute, 2-3minutes, 4-5minutes, 6minutes and over etc..
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    (Original post by byb3)
    anything relating to frequency

    how many people could do a task in 1minute, 2-3minutes, 4-5minutes, 6minutes and over etc..

    Do you know how I would use one if I wanted to represent the BMI's of boys in year 7?
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    (Original post by byb3)
    anything relating to frequency

    how many people could do a task in 1minute, 2-3minutes, 4-5minutes, 6minutes and over etc..
    Yes, that's a good explanation.

    As long as you know how to answer exam questions on Histograms, then that is fine.
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    (Original post by bono)
    Yes, that's a good explanation.

    As long as you know how to answer exam questions on Histograms, then that is fine.
    i hate pigging histograms, with their frequency density and class width intervals and such.
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    (Original post by CHAD)
    Do you know how I would use one if I wanted to represent the BMI's of boys in year 7?
    well seperate the BMI into sensible groups (depends on how much data you have). Then count how many boys fall into each group.
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    (Original post by ]{ingnik)
    i hate pigging histograms, with their frequency density and class width intervals and such.
    Yes I know, that is why i am doing Mechanics instead of Stats for my Maths A-Level!

    (Although when I start Further Maths in June, I'll be doing some Stats modules anyway).
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    (Original post by byb3)
    well seperate the BMI into sensible groups (depends on how much data you have). Then count how many boys fall into each group.

    Cool thanx! so say i seperate it into 3 groups of 2 so
    19-21, 4 boys
    21-23, 5 boys
    23-25, 7 boys
    and draw the histogram.
    What kinda thing wud i say about it?
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    (Original post by CHAD)
    Cool thanx! so say i seperate it into 3 groups of 2 so
    19-21, 4 boys
    21-23, 5 boys
    23-25, 7 boys
    and draw the histogram.
    What kinda thing wud i say about it?
    that it is negatively skewed (look it up if you don't know what it means).
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    I bet ur doing that MAyfield coursework - I'm doing that too... do you know how to draw proper histograms in Excel with unequal class intervals?
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    (Original post by me!)
    I bet ur doing that MAyfield coursework - I'm doing that too... do you know how to draw proper histograms in Excel with unequal class intervals?

    The problem is I have lost all my notes on histograms. Sorry if im bugging ne1, but cw is in 4 2moro and i need it desperately. Yeah, mayfield high cw, unequal class intervals?
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    (Original post by CHAD)
    The problem is I have lost all my notes on histograms. Sorry if im bugging ne1, but cw is in 4 2moro and i need it desperately. Yeah, mayfield high cw, unequal class intervals?
    In a histogram the area of the bar is proportional to the frequency of each class, so on the y axis you have frequency density or the relaitve frequency... I can't get excel to do this... BTW negaitively skewed means that most of the values are high... I think you have to draw the shape of distribution to get the best marks...
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    (Original post by me!)
    In a histogram the area of the bar is proportional to the frequency of each class, so on the y axis you have frequency density or the relaitve frequency... I can't get excel to do this... BTW negaitively skewed means that most of the values are high... I think you have to draw the shape of distribution to get the best marks...

    hi
    thank u sooooo much! frequency density is just the number of people in the classinterval but it is show in area instead of the other way? is the right?
    thanks soooo much!!!!!!
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    (Original post by CHAD)
    hi
    thank u sooooo much! frequency density is just the number of people in the classinterval but it is show in area instead of the other way? is the right?
    thanks soooo much!!!!!!
    Yep… so to work out the height that the bar goes up the y axis you do the frequency divided by the class width, because then when you draw the graph the area of the bar will give you the frequency. For example if a class interval was 0 – 8 with a frequency of 2, the width of the class would be 8, so to get the height of the bar on your histogram you would divide 2 (the frequency) by 8 (the class width), this would give you 0.25, so your bar on the histogram would be 0.25 high. This 0.25 is the frequency density, so if you multiply this frequency density by the class width it gives you the frequency … hope that makes sense.
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    (Original post by me!)
    Yep… so to work out the height that the bar goes up the y axis you do the frequency divided by the class width, because then when you draw the graph the area of the bar will give you the frequency. For example if a class interval was 0 – 8 with a frequency of 2, the width of the class would be 8, so to get the height of the bar on your histogram you would divide 2 (the frequency) by 8 (the class width), this would give you 0.25, so your bar on the histogram would be 0.25 high. This 0.25 is the frequency density, so if you multiply this frequency density by the class width it gives you the frequency … hope that makes sense.

    ahhhh thanks soooo much!!!!!! if u ever want help ask! bearing in mind i may not no, but u no ill try! THANKS!
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    (Original post by CHAD)
    ahhhh thanks soooo much!!!!!! if u ever want help ask! bearing in mind i may not no, but u no ill try! THANKS!
    Hey ur welcome
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    Does anyone know how to draw proper histograms in Excel - it won't let me do proper unequal class intervals...
 
 
 
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