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    How do you do part (d)? Please could you also show all the steps to how you got the answer?
    Thanks!
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    you find the sum from 1 to 200

    then the sum from 1 to 4

    then subtract one from the other ?

    *full solutions are forbidden
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    (Original post by the bear)
    you find the sum from 1 to 200

    then the sum from 1 to 4

    then subtract one from the other ?

    *full solutions are forbidden
    Sorry but I still don't understand?!
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    (Original post by Shanahey)
    Sorry but I still don't understand?!
    okay... that funny spiky letter ( like a W on its side ) that means add up a certain amount of terms... you use it twice..

    firstly to add up from the 1st to the 200th

    secondly to add up from the 1st to the 4th

    by subtracting your answers you find the sum from the 5th to the 200th ?
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    (Original post by the bear)
    okay... that funny spiky letter ( like a W on its side ) that means add up a certain amount of terms... you use it twice..

    firstly to add up from the 1st to the 200th

    secondly to add up from the 1st to the 4th

    by subtracting your answers you find the sum from the 5th to the 200th ?
    Thanks that kinda made more sense now! But how would you add up the terms from the 1st to the 200th?? Is there an easier way you could do this?
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    (Original post by Shanahey)
    Thanks that kinda made more sense now! But how would you add up the terms from the 1st to the 200th?? Is there an easier way you could do this?
    just use the formula in part c) with a suitable value of n ?
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    (Original post by the bear)
    just use the formula in part c) with a suitable value of n ?
    (Original post by MikaelaLR)
    Hope this helps.
    Thanks a bunch!
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    (Original post by Sharingiscaring)
    first find the sum of the first 200 terms: 1/2x200 (2(2)+(200-1)5)= 100x999 =99900
    then because you only want from 5 to 200, you need to subtract the first four terms: 1/2x4(2(2)+(4-1)5)=2x19 =38
    so 99900-38=99862
    sorry if my working out is wrong but I think this is how you do it
    Thanks I worked it out now!
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    Also how would you do part b and c to this question??

    Thank you!
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    Where did you get those questions from
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    (Original post by Exams=stress)
    Where did you get those questions from
    Here's the link https://e376869c6477cc9b0cda8e575d06...c%20series.pdf
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    Have you done Solomon papers?
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    (Original post by Shanahey)
    Also how would you do part b and c to this question??

    Thank you!
    Have you done this one, if so what did you get or could you give me the mark scheme please
 
 
 
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