Variance is _____. a. a measure of the average, or central value ...

[storky111]

Variance is _____.
 a. a measure of the average, or central value of a random variable
  b. a measure of the dispersion of a random variable
  c. the square root of the standard deviation
  d. the sum of the deviation of data elements from the mean

Question 2

At a local university, a sample of 49 evening students was selected in order to determine whether the average age of the students is significantly different from 21 years. The average age of the students in the sample was 23 years with a standard deviation of 3.5 years.
 a. Formulate the hypotheses for this problem.
  b. Compute the test statistic.
  c. Determine the p-value and test these hypotheses. Let  = .05.

[jaaaaaaa]

Answer to Question 1

b

Answer to Question 2

a. H0:  = 21 years
Ha:   21 years
b. t = 4
c. p-value is almost zero; therefore, reject H0

[storky111]

Gracias!

[amandanbreshears]

Wow, this really help