Recent content by weiji

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    Undergrad A town has 6 parks. One day, 6 friends, who are unaware of each

    Yea, me too. By the way, do you know anything about mathematical modeling?
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    Undergrad A town has 6 parks. One day, 6 friends, who are unaware of each

    Yes, I got it. Thanks. The total ways they can go to parks are 6^(6), because 6 persons, each person has 6 options. Then event B, it would be 6! ways. Therefore the solution is 1 - (6!/6^6). Thanks again, tiny-tim. I am picking up a probability course for this semester, and I am really thankful...
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    Undergrad A town has 6 parks. One day, 6 friends, who are unaware of each

    A town has 6 parks. One day, 6 friends, who are unaware of each other's decision, choose a park randomly and go there at the same time. What is the probability that at least 2 of them go to the same park? Any idea for this kind of question? I have an idea, but I don't know how to put in a...
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    High School Divisors of 55,125: Counting Principle

    Thanks for sharing. By the way, I'm new here and nice to meet you all.
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    High School Divisors of 55,125: Counting Principle

    I did a very long calculation by assume a=1, b=1 ; a=1,c=1 ; b=1,c=1, from here, I know 1575x35 = 2625x21 = 3675x15. Then I calculate each possible answer, I got 36 divisors. But is there any faster way? I really have no idea. :(
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    High School Divisors of 55,125: Counting Principle

    How many divisors does 55,125 have? For example, 55,125 = (3)^2 . (5)^3 . (7)^2