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Akshay_Budhkar
satellite plz help with the probability question!!!!
hello.. i tried it.. no use
link isn't working for me
we can solve here
a rod is divided in 4 parts.. probability that it is a quadrilateral?
ok it is the same problem as last time yes?
not sure what you mean. i meant use the second proof in the paper i sent you. not the volume one, but the line segment one.
start an page 186 at the line "construction of an n-gon will be impossible of AB is longer than 1/2" do you see where i mean?
of course replace n by 4
i may be easier to do this in chat, or quicker, but i can write the idea of the proof here. i am just mimicking the proof i sent you in the pfd .
you can come in chat?
you have a "rod" stick whatever and you are going to break it into 4 parts by picking 3 points uniformly at random, and the question is what is the probability that you can make a quadrilateral
you already know the answer is 1/2 so far correct. so we just need the proof
first trick to to say that the rod has length one so we can dispense with ratios
so it looks something like this 0 --------------a-----------------b--------------------------c-------------------------1 where a, b, c are the points chosen at random to break up the rod
now the question is "when would you not get a quadrilateral\"
now i am just reading along what i sent, replacing n by 4
construction of a quadtrilateral will be impossible if \[\overline{0a}\] is bigger than one half, i.e. if all three points are to the right of the midpoint of the segment. the probability that one is to the right is 1/2 and all three to the right would be \[(\frac{1}{2})^3\]
the same is true for the other three segments, and the probability that each of them is bigger than one half is also 1/8 so the probability of failure is 4 times 1/8 = 1/2 and therefore so is the probability of success.