Question

I am having trouble deciding what is true for these questions. I thought I had the right answers but they keep getting marked wrong. For Question 1, I chose option 2, as I though all the others to be false. For Question 4 I chose option 4, as I learned that the z-scores of the mean and standard deviation were always 0 and 1, respectively. For question 5 I chose option 4 as well.

Which one of the following statements is true?

Question 1 options:

	If the standard deviation of a data set is 0, the median will also be 0.
	If a sample of size 3 is made up of 3 consecutive whole numbers, the standard deviation will be 1.
	The line in the box of the boxplot is always exactly halfway between the first and third quartiles.
	The third quartile of a data set can be less than first quartile.
	Boxplots are the best type of plot for illustrating the shape of the distribution.

Suppose we took the age, in years, of every student currently enrolled in STAT*2040 DE, and calculated the z-score for each student. We then calculated the mean and standard deviation of these z-scores. Which one of the following statements is true?

Question 4 options:

	The mean and standard deviation of the z-scores would both be 0.
	The mean of the z-scores would be 0, but it is impossible to know what the standard deviation of the z-scores would be without knowing what the ages are.
	The mean z-score would be the same as the mean age, and the standard deviation of the z-scores would be the same as the standard deviation of the ages.
	The mean z-score would be 0, and the standard deviation of the z-scores would be 1.
	The mean z-score would be the same as the mean of the ages, and the standard deviation of the z-scores would be 1.

Which one of the following statements is true?

Question 5 options:

	Outliers can never have a negative value.
	If all values in a data set are positive, the mean cannot be less than the standard deviation.
	If all values in a data set are positive, the mean cannot be less than the median.
	The interquartile range is a descriptive measure of centre.
	The units of the standard deviation are the same as the units of the original variable.

Answer 1

Which one of the following statements is true?

Ans 1)

Boxplots are the best type of plot for illustrating the shape of the distribution.

Suppose we took the age, in years, of every student currently enrolled in STAT*2040 DE, and calculated the z-score for each student. We then calculated the mean and standard deviation of these z-scores. Which one of the following statements is true?

Ans 4 )  The mean z-score would be the same as the mean age, and the standard deviation of the z-scores would be the same as the standard deviation of the ages.

Which one of the following statements is true?

Ans 5 )

The units of the standard deviation are the same as the units of the original variable.