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Probability question!?. Is the answer given actually correct? watch

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    Long story short, I got my hands on probability questions with answers. But is this answer correct for this question? to me it isn't.

    Roger is competing in a 1,000 meter run with eight competitors. Frederick, the runner with the best results from the last race, will get the best starting position. A computer will randomly select the other runners’ positions. What is the probability that Jason will get the least favorable position?
    a) 1/9 (.11)
    b) 1/8 (.13)*
    c) 1/7 (.14)
    d) 7/8 (.88)
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    No it's1/7

    Look at it like this their are 8 different coloured balls in a bag Frederick takes the red one and keeps it what is the possibility of Rodger getting the blue one (if their is only 1 blue ball) it's how many of the item their are (in this case 1) over how many their are in total after Frederick takes his one.

    So 1/7
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    (Original post by natalie427)
    Long story short, I got my hands on probability questions with answers. But is this answer correct for this question? to me it isn't.

    Roger is competing in a 1,000 meter run with eight competitors. Frederick, the runner with the best results from the last race, will get the best starting position. A computer will randomly select the other runners’ positions. What is the probability that Jason will get the least favorable position?
    a) 1/9 (.11)
    b) 1/8 (.13)*
    c) 1/7 (.14)
    d) 7/8 (.88)
    It isn't. The fact that it guarantees one of them will get the best starting position get's rid off one of the people who are eligible for the worst starting position. Answer is 1/7 as it leaves 7 possibilities.
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    Exactly what I thought. I'll have to email my sup.
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    (Original post by natalie427)
    Exactly what I thought. I'll have to email my sup.
    It could however been a case of misunderstanding. When the first sentence says "Roger is competing in a 1000m run with either competitors" it could mean that Roger is the 9th one which would make the original answer correct, but that is something the question should explicitly state as everyone would assume that Roger is part of that 8 person group by the way it is worded.
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    (Original post by RDKGames)
    It could however been a case of misunderstanding. When the first sentence says "Roger is competing in a 1000m run with either competitors" it could mean that Roger is the 9th one which would make the original answer correct, but that is something the question should explicitly state as everyone would assume that Roger is part of that 8 person group by the way it is worded.

    Yeah I'm gonna question him on that, like why do we need to know that first bit really? Odd question with an odd answer
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    The fact that 1/9th is an option makes me think that was the intended meaning
 
 
 
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