Hey there! Sign in to join this conversationNew here? Join for free
    Offline

    12
    ReputationRep:
    (Original post by wenqi.s)
    I came across Cartesian grids in the spec. Does anyone know how they work?? It says 'understand and use Venn diagrams and Cartesian grids'. I know how to use Venn diagrams but Cartesian grids I don't so plz can someone explain this to me??
    Cartesian grids are another word for sample space diagrams
    Offline

    1
    ReputationRep:
    Can someone plz tell me the advantages of a questionnaire and how to interpret srrc plz tx
    Offline

    18
    ReputationRep:
    (Original post by wenqi.s)
    I think my teacher didn't teach me half the content
    Same here we had one week to learn everything although it's very do able
    Offline

    0
    ReputationRep:
    I'm new to a school and i am taking the stats paper but I have no coursework. What would I need to get even a C grade.
    Offline

    0
    ReputationRep:
    (Original post by nisha.sri)
    True !!
    No doubt it'll come up tomorrow
    Offline

    18
    ReputationRep:
    (Original post by hkirkpatrick)
    No doubt it'll come up tomorrow
    Hey there could you help me out with this question

    On two farms there are pigs that are 20 weeks old. On each farm the weights of the pigs are assumed to be normally distributed.

    Farm A - Mean weight is 85 and Standard deviation is 2.5.

    Draw the graph.
    Offline

    1
    ReputationRep:
    Can u just tell me the adv of questionnaires
    Offline

    0
    ReputationRep:
    If you are struggling with any topics there is a really good teacher who goes through them in hour long videos. Just speed the video up to the maximum if you are short on time
    Offline

    18
    ReputationRep:
    (Original post by Amnotsure)
    Can u just tell me the adv of questionnaires
    Cheaper
    Quicker to analyse
    Easy to categorise
    Offline

    18
    ReputationRep:
    Anyone could you help me with this question

    On two farms there are pigs that are 20 weeks old. On each farm the weights of the pigs are assumed to be normally distributed.

    Farm A - Mean weight is 85 and Standard deviation is 2.5.

    Draw the graph.
    Offline

    16
    ReputationRep:
    They are cheap and easy. Plus you can have large numbers of participants.
    Offline

    16
    ReputationRep:
    (Original post by nisha.sri)
    Anyone could you help me with this question

    On two farms there are pigs that are 20 weeks old. On each farm the weights of the pigs are assumed to be normally distributed.

    Farm A - Mean weight is 85 and Standard deviation is 2.5.

    Draw the graph.
    I cant draw the graph here and it is quite hard to help you.

    It is like a bell shape. The peak is the mean. Under the bell the population.Standard deviation shows how spread out it is. By standard deviation 3, the part of the bell should be nearly touching the x axis. Consult your wrokbook or google for further help.

    remember these numbers:

    SD1 and -1 should cover 68% of the population
    SD2 and -2 should cover 95% of the population
    SD3 and -3 should cover 99% of the population
    Offline

    18
    ReputationRep:
    (Original post by stoyfan)
    I cant draw the graph here and it is quite hard to help you.

    It is like a bell shape. The peak is the mean. Under the bell the population.Standard deviation shows how spread out it is. By standard deviation 3, the part of the bell should be nearly touching the x axis. Consult your wrokbook or google for further help.
    Oh ok i understand everything except from the Standard deviation of 3 - where did you get that from ?
    Offline

    1
    ReputationRep:
    (Original post by nisha.sri)
    Cheaper
    Quicker to analyse
    Easy to categorise
    Are you sure cuz that wasn't what the mark scheme said and I'm just confused as that is what my textbook said but in the 2013 ms it was a faster way to collect lots of data
    Offline

    16
    ReputationRep:
    Ahhh. The 3rd standard deviation means 3 standard deviations away from the mean (on both sides of the mean).

    So it is: 85+2.5*3=92.5
    and:85-2.5*3=77.5
    Offline

    16
    ReputationRep:
    (Original post by Amnotsure)
    Are you sure cuz that wasn't what the mark scheme said and I'm just confused as that is what my textbook said but in the 2013 ms it was a faster way to collect lots of data
    It should be multiple choice.
    Offline

    18
    ReputationRep:
    (Original post by stoyfan)
    Ahhh. The 3rd standard deviation means 3 standard deviations away from the mean (on both sides of the mean).

    So it is: 85+2.5*3=92.5
    and:85-2.5*3=77.5
    I get what your saying but where does the 3 come from ?! It's not in the question
    Offline

    18
    ReputationRep:
    (Original post by Amnotsure)
    Are you sure cuz that wasn't what the mark scheme said and I'm just confused as that is what my textbook said but in the 2013 ms it was a faster way to collect lots of data
    Which exam board do you do ?
    Offline

    1
    ReputationRep:
    (Original post by stoyfan)
    It should be multiple choice.
    Yh but quicker to analyse or easy to analyse want there so......
    Offline

    16
    ReputationRep:
    It isn't but it should be a reference point to where the pattern of the bell shape should end and start (flatten out). My teacher said that they would be precisely seeing if your graph is correct, but they will see if the graph flattens our at the correct point.
 
 
 
  • See more of what you like on The Student Room

    You can personalise what you see on TSR. Tell us a little about yourself to get started.

  • Poll
    Has a teacher ever helped you cheat?
  • See more of what you like on The Student Room

    You can personalise what you see on TSR. Tell us a little about yourself to get started.

  • The Student Room, Get Revising and Marked by Teachers are trading names of The Student Room Group Ltd.

    Register Number: 04666380 (England and Wales), VAT No. 806 8067 22 Registered Office: International House, Queens Road, Brighton, BN1 3XE

    Write a reply...
    Reply
    Hide
    Reputation gems: You get these gems as you gain rep from other members for making good contributions and giving helpful advice.