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    This may well seem too simple but how would i work out the probability of rolling a "4" and then a "6". using P(4 or 6)=P(4) + P(6). Using this i came to the answer of 2/6 but that would mean that the probability is now greater than rolling just one 4 or 6. or am i confusing myself? shouldn't i be multiplying 1/6 * 1/6 or is that something else?
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    it's 1/6 * 1/6 so 1/36

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    P(4 or 6) is not equal to P(4) -> P(6) (as in rolling one then the other)
    P(4 or 6) would be the probability of rolling either a 4 or a 6 given only one roll.
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    (Original post by Salman_)
    it's 1/6 * 1/6 so 1/36

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    yes but how so? can you please analyse this formula for me?


    p(a or b)= p(A) + p(B)

    why is this a plus and not a multiplication symbol?
    i'm very confused.

    the "+" is what's confusing me.
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    I don't know why, I just know the answer. sorry.

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    (Original post by WarHammer-)
    yes but how so? can you please analyse this formula for me?


    p(a or b)= p(A) + p(B)

    why is this a plus and not a multiplication symbol?
    i'm very confused.

    the "+" is what's confusing me.
    Take this example,
    On a fair dice, you have 6 possible outcomes. If you throw the dice, what is the probability that you'll land on either a 1 or 2 or 3 or 4 or 5 or 6?
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    (Original post by Salman_)
    I don't know why, I just know the answer. sorry.

    Sent from my XT1032 using Tapatalk
    That's quite alright mate! i had the same answer as you but i just didn't know why! lol someone might explain this phenomenon to me if not you!

    thanks for trying.
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    (Original post by IDontKnowReally)
    Take this example,
    On a fair dice, you have 6 possible outcomes. If you throw the dice, what is the probability that you'll land on either a 1 or 2 or 3 or 4 or 5 or 6?



    1/6.
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    (Original post by WarHammer-)
    1/6.
    What must the total probability add up to?
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    (Original post by IDontKnowReally)
    What must the total probability add up to?
    6.
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    (Original post by WarHammer-)
    6.
    No. The total probability always adds up to 1. Your teacher should have taught you this?
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    (Original post by IDontKnowReally)
    No. The total probability always adds up to 1. Your teacher should have taught you this?
    oh yes i know that sorry my bad.
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    (Original post by WarHammer-)
    oh yes i know that sorry my bad.
    Okay, so you know that the probability of each outcome is 1/6, and the total probability adds up to 1.
    You also know that there are 6 possible outcomes.
    Everytime you roll a dice you get one of those outcomes (you get a 1 OR you get a 2 OR a 3 OR 4 OR 5 OR 6).
    1/6 + 1/6 + 1/6 +... = 1
    so P(1 OR 2 OR 3 OR 4 OR 5 OR 6) =1
    Does this answer your question ?
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    (Original post by IDontKnowReally)
    Okay, so you know that the probability of each outcome is 1/6, and the total probability adds up to 1.
    You also know that there are 6 possible outcomes.
    Everytime you roll a dice you get one of those outcomes (you get a 1 OR you get a 2 OR a 3 OR 4 OR 5 OR 6).
    1/6 + 1/6 + 1/6 +... = 1
    so P(1 OR 2 OR 3 OR 4 OR 5 OR 6) =1
    Does this answer your question ?
    so is post number 2 correct?
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    (Original post by WarHammer-)
    so is post number 2 correct?
    Yes, it is. Do you understand why?
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    [QUOTE=IDontKnowReally;68398152]Yes, it is. Do you understand why?[/QUOTE



    (1/6)^2 because of two activities going on?
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    [QUOTE=WarHammer-;68398236]
    (Original post by IDontKnowReally)
    Yes, it is. Do you understand why?[/QUOTE



    (1/6)^2 because of two activities going on?
    Yes
 
 
 
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