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    You decide to take the stairs and to climb either 1 or 2 stairs at a time, at any given time. In how many different ways can you get up a flight of 11 stairs? Prove your answer.

    I got 56 different ways
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    (Original post by Heisenberg 23)
    You decide to take the stairs and to climb either 1 or 2 stairs at a time, at any given time. In how many different ways can you get up a flight of 11 stairs? Prove your answer.

    I got 56 different ways
    CSAT, eh?

    I'll do it and get back to you; :-)
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    (Original post by Heisenberg 23)
    You decide to take the stairs and to climb either 1 or 2 stairs at a time, at any given time. In how many different ways can you get up a flight of 11 stairs? Prove your answer.

    I got 56 different ways
    56 doesn't seem correct, you may one to do the number of ways to go down 1 step, 2 steps, 3 steps, 4 steps and see if you can spot a pattern. (hint: recurrence)
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    Aren't we not supposed to discus CSAT answers? Zacken did you get my PM?
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    (Original post by Louisb19)
    Aren't we not supposed to discus CSAT answers? Zacken did you get my PM?
    Oh sheeet, really? I didn't know that! :eek:
    I'm replying to it now. :-)
    Edit: Sent it off.
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    (Original post by Louisb19)
    Aren't we not supposed to discus CSAT answers? Zacken did you get my PM?
    Nah this is just a practice test, not a real test. And I'm in Yr 11. I was just wondering
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    (Original post by Heisenberg 23)
    Nah this is just a practice test, not a real test. And I'm in Yr 11. I was just wondering
    Did you get my hint? Ring any bells? Perhaps a familiar recurrence concerning rabbits?
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    (Original post by Zacken)
    Did you get my hint? Ring any bells? Perhaps a familiar recurrence concerning rabbits?
    I haven't got a clue to what your hinting at. How did you work it out And whats your answer
    I'm probably being dumb XD
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    (Original post by Zacken)
    Oh sheeet, really? I didn't know that! :eek:
    I'm replying to it now. :-)
    Edit: Sent it off.
    I'm not to sure, my friend is a compsci applicant and he said that the people are Cambridge are not telling them the answers to the practice questions.
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    (Original post by Louisb19)
    I'm not to sure, my friend is a compsci applicant and he said that the people are Cambridge are not telling them the answers to the practice questions.
    Its a sample question, so discussing answers for these are allowed. I just wanted to know how to do it
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    (Original post by Louisb19)
    I'm not to sure, my friend is a compsci applicant and he said that the people are Cambridge are not telling them the answers to the practice questions.
    I just checked the web-page out and it seems fine? They said you can't discuss the actual test questions, but the practice ones should be good?

    Did you get my PM?

    (Original post by Heisenberg 23)
    I haven't got a clue to what your hinting at. How did you work it out And whats your answer
    I'm probably being dumb XD
    1 step: 1 = 1 way
    2 steps: 1, 1 or 2 = 2 ways
    3 steps: 1,1,1 - 1, 2 - 2, 1 = 3 ways
    4 steps: 1, 1, 1, 1 - ... = 5 ways
    5 steps: 1, 1, 1, 1, 1 - ... = 8 ways

    So no of ways is 1, 2, 3, 5, 8 as the number of steps increase? Have you heard of the Fibonacci sequence?
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    (Original post by Zacken)
    I just checked the web-page out and it seems fine? They said you can't discuss the actual test questions, but the practice ones should be good?

    Did you get my PM?
    Alright that's fine then. Yeah I did. I replied
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    (Original post by Zacken)
    I just checked the web-page out and it seems fine? They said you can't discuss the actual test questions, but the practice ones should be good?

    Did you get my PM?



    1 step: 1 = 1 way
    2 steps: 1, 1 or 2 = 2 ways
    3 steps: 1,1,1 - 1, 2 - 2, 1 = 3 ways
    4 steps: 1, 1, 1, 1 - ... = 5 ways
    5 steps: 1, 1, 1, 1, 1 - ... = 8 ways

    So no of ways is 1, 2, 3, 5, 8 as the number of steps increase? Have you heard of the Fibonacci sequence?
    I haven't heard of that, but I'll search it up. Thanks for the help Zacken.
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    (Original post by Heisenberg 23)
    I haven't heard of that, but I'll search it up. Thanks for the help Zacken.
    It's super cool.
 
 
 
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