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    A sequence begins:
    1, 2, 3, 4, 5, 1, 2, 3, 4, 5.

    and continues the pattern. What is the 48th term? This is a geometric, periodic sequence isn't it, with a period of 5? That makes the first term 1, I can't work out the common ratio. What is it?
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    Actually, this kind of question doesn't need to be approached in a complicated way at all. Note that the 5th term is 5, the 10th term is 5, the 15th term is 5... What is the 45th term? Can you see how you can then easily work out the 48th term?
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    (Original post by Noble.)
    Actually, this kind of question doesn't need to be approached in a complicated way at all. Note that the 5th term is 5, the 10th term is 5, the 15th term is 5... What is the 45th term? Can you see how you can then easily work out the 48th term?
    One more question, was I right in saying this was a periodic sequence? Is it arithmetic or geometric?
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    (Original post by Magenta96)
    One more question, was I right in saying this was a periodic sequence? Is it arithmetic or geometric?
    It isn't either arithmetic or geometric, as there's no common difference or ratio.

    To answer the sum of the first 48 terms:

    What's the sum of the first 5 terms? Sum of the first 10 terms? Sum of the first 15 terms? Do you see a pattern emerging?
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    (Original post by Noble.)
    It isn't either arithmetic or geometric, as there's no common difference or ratio.

    To answer the sum of the first 48 terms:

    What's the sum of the first 5 terms? Sum of the first 10 terms? Sum of the first 15 terms? Do you see a pattern emerging?
    oh right yeah that's why I was getting confused as it wouldn't fit into an arithmetic/geometric category. Yes, I've managed to get the right answer now, thank you.
 
 
 
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