Recent content by helix999

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    Normal Distribution Question. Need help

    The solution I have with me is: Prob(mean - 2*σ < X < mean + 1.5*σ) = (0.5 - 0.0228) + (0.5 - 0.0668) My question is how we got (0.5 - 0.0228) + (0.5 - 0.0668) ?
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    Normal Distribution Question. Need help

    [MENTOR note] Post moved from General Math forum hence no template. Assume that a random variable follows a normal distribution with a mean of 80 and a standard deviation of 24. What percentage of this distribution is not between 32 and 116? My approach is to calculate the Probability for (mean...
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    Expectation and Standard Deviation(SD)

    ok i got the examples when SD[x1]<=SD[x2]. But when SD[x1>=Sd[x2]?
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    Expectation and Standard Deviation(SD)

    zero.
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    Expectation and Standard Deviation(SD)

    yeah, the given condition is for every outcome. I think E[x1]<=E[x2] but no idea abt std deviation. i don't know if i am correct.
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    Expectation and Standard Deviation(SD)

    Hi I have a question. Let X1 & X2 be stochastic variables and X1<=X2, then can we say E[X1]<=E[X2] or SD[X1]<=SD[X2]? why or why not? Looking forward to some reply Thanks!
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    Differential equations origin graph

    Fine...i got it.
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    What Are the Possible Dimensions of V Intersection W in R4?

    then how do we solve such integrals
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    Differential equations origin graph

    The question I have is Which graph most closely represents the graph of a solution to the differential equation dy/dx=1+y^4? I have 5 graphs as options. I have doubt in two. Both are same except one is passing thru origin & the other is not. The correct answer is the graph which is passing...
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    Possible Rings with Product of Nonzero Elements Equal to 0?

    it is 3rd one
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    Possible Rings with Product of Nonzero Elements Equal to 0?

    I have just tried to find out some good online tutorials on Rings. When I think of rings, an empty circle comes to my mind...nothing else. I want to know the explanations of each & every points mentioned above otherwise I wouldn't have written them because I have the correct answer.
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    Good basic isomorphism online tutorials

    How the group of symmetries of the regular pentagram is isomorphic to the dihedral group of order 10? Suggest me some good basic isomorphism online tutorial.
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    The circle can be parametrized

    Thnx for the solutions!
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    Find the minimal distance between any point on the sphere

    well...yes...i have a math exam tomorrow...have to finish a LOT of things
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    Possible Rings with Product of Nonzero Elements Equal to 0?

    for which of the following rings is it possible for the product of two nonzero elements to be 0? 1. ring of complex numbers 2. ring of integers modulo 11 3. the ring of continuous real-valued functions on [0,1] 4. the ring {a+b(sqrt(2)) : a & b are rational numbers} 5...