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Math Help - a box of paper

  1. #1
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    Question a box of paper

    A box contains 25 slips of paper numbered 1 to 25. What is the probability that one will randomly select a number that is divisible by 3 or 7?
    help me anybody.....
    I'll be very appresiate you!
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  2. #2
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    Quote Originally Posted by busyboy View Post
    A box contains 25 slips of paper numbered 1 to 25. What is the probability that one will randomly select a number that is divisible by 3 or 7?
    help me anybody.....
    I'll be very appresiate you!
    Write out all the numbers between 1 and 25 that are divisible by either 3 or 7. Count how many there are. Divide that number by 25. Viola!
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  3. #3
    Moo
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    Quote Originally Posted by mr fantastic View Post
    Viola!


    Jhevon made the same mistake !
    It's voilą
    Viol...means rape ! but don't worry, I would give my consent xD
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  4. #4
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    Quote Originally Posted by busyboy View Post
    A box contains 25 slips of paper numbered 1 to 25. What is the probability that one will randomly select a number that is divisible by 3 or 7?
    help me anybody.....
    I'll be very appresiate you!
    A number divisible by 3 is = 3, 6, 9, 12, 15, 18, 21, 24
    = total 8 numbers.

    A number divisible by 7 is = 7, 14, 21
    = total 3 numbers.

    Probability that a number divisible by 3 or 7 is = \frac {8+3}{25}

    = \frac {11}{25}
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  5. #5
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    Quote Originally Posted by Shyam View Post
    A number divisible by 3 is = 3, 6, 9, 12, 15, 18, 21, 24
    = total 8 numbers.

    A number divisible by 7 is = 7, 14, 21
    = total 3 numbers.
    Shyam, if you are going to simply handout complete solutions at least do them correctly.
    Probability that a number divisible by 3 or 7 is = \frac {8+3{\color{red}-1}}{25} = \frac {10}{25}
    You counted 21 twice.
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  6. #6
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    Quote Originally Posted by Moo View Post


    Jhevon made the same mistake !
    It's voilą
    Viol...means rape ! but don't worry, I would give my consent xD
    The viola is my favourite instrument. I like to hear it sometimes when I post. Hence my deliberate transposition of letters. As for Jhevon, I think he's just lousy at French
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