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Questions 1. (10 Points) What is a random variable? 2. (5 Points) Why do random variables have sampling distributions? 3. (10 Points) What are the two ways to measure the central tendency of the distribution a random variable? Define them 4. (5 Points) When will the two measures of central tendency be equal to each other? 5. (5 Points) When will the two measures of central tendency be unequal? 6. (10 Points) What is a variance? 7. (5 Points) Which measure of central tendency is the variance related to? 8. (2.5 Points) If two random variables are measured in different units, are the variances directly comparable? 9. (2.5 Points) Assume that you draw two random samples of the same variable from two different populations. If the variance in the sample from population 1 is bigger than population 2, but the means are the same, what does this tell you about the two populations? 10. Use the table to answer the following questions:

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Answer #1
  1. Random variable has been defined as a function which assumes real values on the outcomes of a random experiment.In repeated performances of the random experiment,the random variable will in general assume different values with a definite probability associated with each value or interval of values.
  2. Variables are obtaining certain values when the values of variables are determined by the probability they are called random variables. In the sampling distribution mean has a normal shape if the population from which the samples are drawn are normal.

xn be a simple xandom uloti Du a n stondard deviation The Handl ou vaHiabb i i uw Li MOH th a mean Vandl standavd oluviaton

3. The most common measures of central tendency are the arithmetic mean,the median and the mode.

Mean oH OveH CL and C He calculaTeal by the o llool and X eol una HO u lnascendng denMediau lo Ll mula Modle the value thar

4.If the distribution is symmetric then the mean is equal to the median and the distribution will have zero skewness.

6)Variance is the measure of the spread between numbers in a data set.Formula for variance is

  

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