Ask Question
27 January, 06:19

Let X be a normally distributed random variable with a mean of 20 and a standard deviation of 2.25. Using Excel, find the proportion of the values of X that are less than 21.

+3
Answers (1)
  1. 27 January, 06:46
    0
    Answer: The normal distribution is the most important distribution. It describes well the

    distribution of random variables that arise in practice, such as the heights or weights

    of people, the total annual sales of a firm, exam scores etc. Also, it is important for the

    central limit theorem, the approximation of other distributions such as the binomial,

    etc.

    • We say that a random variable X follows the normal distribution if the probability

    density function of X is given by

    f (x) = 1

    σ





    e

    - 1

    2

    (

    x-µ

    σ

    )

    2

    , - ∞ < x < ∞

    This is a bell-shaped curve.

    • We write X ∼ N (µ, σ). We read: X follows the normal distribution (or X is normally

    distributed) with mean µ, and standard deviation σ.
Know the Answer?
Not Sure About the Answer?
Find an answer to your question 👍 “Let X be a normally distributed random variable with a mean of 20 and a standard deviation of 2.25. Using Excel, find the proportion of the ...” in 📗 Mathematics if the answers seem to be not correct or there’s no answer. Try a smart search to find answers to similar questions.
Search for Other Answers