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    Hey I read this question and I want to figure out how to work it out
    basically it says that in 2001 there was 2 rabbits and in 2002 there was 4 rabbits and in 2003 there was 8 rabbits

    which means that it doubles every year but what year will it be when there is 1 million rabbits?

    I know the answer is 2020 but how do I get there?
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    (Original post by high)
    Hey I read this question and I want to figure out how to work it out
    basically it says that in 2001 there was 2 rabbits and in 2002 there was 4 rabbits and in 2003 there was 8 rabbits

    which means that it doubles every year but what year will it be when there is 1 million rabbits?

    I know the answer is 2020 but how do I get there?
    show it in calculations
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    Keep doubling until you get to a million. (Takes a long time, worth the marks though)
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    Lol I know I could do that but isn't there a method?
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    if you havent done sequences or logs, then i cant think of any other way. i dont think sequences or logarithms are on the gcse syllabus, are they?
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    Doable with logs. Without that just do it longhand. It's GCSE. If you put the answer down without writing anything you'd probably still get the marks.
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    (Original post by RK92)
    if you havent done sequences or logs, then i cant think of any other way. i dont think sequences or logarithms are on the gcse syllabus, are they?
    Nope they're not but I can still do them lol...
    so would it be log2 1000000?
    Thanks a lot never thought it would come in handy....
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    the bunnies would all be inbred and genetically broken
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    (Original post by sparrow-legs)
    the bunnies would all be inbred and genetically broken
    XD that made my day!
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    The sequence is 2 to the power n.

    You want 1000000 rabbits so
    2^n = 1000000

    Taking logs of both sides

    nlog2 = log1000000

    therefore n= (log1000000)/(log2)

    Add the answer to 2000 to get the year since you started in 2001

    EDIT: or use log to the base 2 as you stated. Makes it a bit simpler.
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    (Original post by high)
    Nope they're not but I can still do them lol...
    so would it be log2 1000000?
    Thanks a lot never thought it would come in handy....
    yeah, it would be log base 2 of 1,000,000 which is approx 19.9years so youd say 2020
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    If you let 2001, 2002, 2003 etc = 1, 2, 3 etc. and call this number (set) as n, then x (the answer) is 2 to the power of n. (2^n)

    so 1mil = 2 ^ y y is an unknown value of n
    log both sides to get log(1mil)=ylog(2)

    log(1mil) / log (2) =y
    y- 19.93 = 20
    so 2000+20 = 2020
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    2001 - 2^1
    2002 - 2^2
    2003 - 2^3....

    X - 2^20 ( about 1 million)

    so x=2020
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    2^n = 1000000

    Just work it out. They won't ask for more in GCSE.
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    Assuming that there were 2 rabbits at the beginning of 2001 and 4 at the beginning of 2002 etc. then there will 1,000,000 rabbits by midway through December in 2019, not 2020.
 
 
 
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