Question

In: Statistics and Probability

X ~ N(50, 13). Suppose that you form random samples of 25 from this distribution. Let...

X ~ N(50, 13). Suppose that you form random samples of 25 from this distribution. Let X be the random variable of averages. Let ΣX be the random variable of sums.

  • Part (a)

    Sketch the distributions of X and X on the same graph.
    • A B)
      C)D)
  • Part (b)

    Give the distribution of X. (Enter an exact number as an integer, fraction, or decimal.)

    X ~ ____(____,____)

  • Part (c)

    Sketch the graph, shade the region, label and scale the horizontal axis for X, and find the probability. (Round your answer to four decimal places.)

    P(X < 50) = ________

  • Part (d)

    Find the 30th percentile. (Round your answer to two decimal places.)

  • _________.

  • Part (e)

    Sketch the graph, shade the region, label and scale the horizontal axis for X, and find the probability. (Round your answer to four decimal places.)

    P(48 < X < 54) = _________

  • Part (f)

    Sketch the graph, shade the region, label and scale the horizontal axis for X, and find the probability. (Round your answer to four decimal places.)

    P(17 < X < 48) = ___________

  • Part (g)

    Give the distribution of ΣX.
    ΣX ~ ______(_____,_____)
  • Part (h)

    Find the minimum value for the upper quartile for ΣX. (Round your answer to two decimal places.)

  • ________.

  • Part (i)

    Sketch the graph, shade the region, label and scale the horizontal axis for ΣX, and find the probability. (Round your answer to four decimal places.)

    P(1200 < ΣX < 1350) = ___________

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