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

    0
    ReputationRep:
    Can anyone help on this question I'm struggling with, its standard deviation the biology one, so n-1.
    It says to work out the SD of 6 prices: 86p, 88p, 84p, 79p, 81p and 86p.
    I worked it out to be 0.04, and used 0.86, 0.88 etc in my calculator, and I'm not sure whether i just use 86 as itself.
    It then says another 6 prices have a mean of 87p and a standard deviation of 5.2 pence and to compare them, but my SD was nowhere close?
    Have i gone wrong somewhere?
    Offline

    20
    ReputationRep:
    For the first one, was your standard deviation 4p or 0.04p? The 4p is not far out, but redo the calculation to get the correct answer.
    • Thread Starter
    Offline

    0
    ReputationRep:
    (Original post by morgan8002)
    For the first one, was your standard deviation 4p or 0.04p? The 4p is not far out, but redo the calculation to get the correct answer.
    I worked the overall SD to be 0.04, and for 86p I got 0.02 then squared it to 0.0004?
    Offline

    16
    ReputationRep:
    (Original post by Shani148)
    I worked the overall SD to be 0.04, and for 86p I got 0.02 then squared it to 0.0004?
    Standard deviation is the square root of variance


    Posted from TSR Mobile
 
 
 
  • 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.