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    How would you find P?
    (Yes I have looked at the mark scheme- I don't really understand it)
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    2p/(12-p)=(4p-5)/2p. You then cross multiply and solve the quadratic equation 😀
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    (Original post by Questioness)
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    How would you find P?
    (Yes I have looked at the mark scheme- I don't really understand get it)
    It's an arithmetic series, so the difference between the second and third term is the same as the difference between the second and first term (i.e: common difference).

    What is the difference between the first and second term? (Second - first)

    What is the diffence between the second and third term (third - first)

    Equate those to get an equation involving p which you can then solve.
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    (Original post by Zacken)
    It's an arithmetic series, so the difference between the second and third term is the same as the difference between the second and first term (i.e: common difference).

    What is the difference between the first and second term? (Second - first)

    What is the diffence between the second and third term (third - first)

    Equate those to get an equation involving p which you can then solve.
    Okay, thanks for the explanation .
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    (Original post by Questioness)
    Okay, thanks for the explanation .
    No problem.
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    (Original post by Cardboard5678)
    2p/(12-p)=(4p-5)/2p. You then cross multiply and solve the quadratic equation 😀
    That's the method for a geometric sequence, not an arithmetic one
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    (Original post by Fangedbeast)
    That's the method for a geometric sequence, not an arithmetic one
    Oh yeah. Oops just been revising c2. It's subtract rather then divide then 😳
 
 
 
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