Question 1

Based on the Empirical Rule,what percent of the observations will lie between plus or minus two standard deviations from the mean?

Accepted Answer

The Empirical Rule states that approximately 68% of observations will fall within one standard deviation of the mean, 95% within two standard deviations of the mean, and 99.7% within three standard deviations of the mean. Therefore, the answer is A) 95%.

Question 2

A sample of assistant professors on the business faculty at state supported institutions in Ohio revealed the mean income to be $72,000 for 9 months with a standard deviation of $3,000.Using Chebyshev's Theorem,what proportion of the faculty earns more than $66,000 but less than $78,000?

Accepted Answer

The answer of A sample of assistant professors on the...

Question 3

The weights (in grams)of the contents of several small bottles are 4,2,5,4,5,2 and 6.What is the sample variance?

Accepted Answer

The answer of The weights (in grams)of the contents of...

Question 4

A small manufacturing company with 52 employees has annual salaries distributed such that the mean is $25,459,the median is $24,798 and the mode is $24,000.An additional foreman is hired at an annual salary of $50,700.What measure of central location that is most affected by the addition of this salary? ____________________.

Accepted Answer

The answer of A small manufacturing company with 52 employees...

Question 5

What measure of central location cannot be determined if the distribution has an open-ended class? _____________________.

Accepted Answer

The answer of What measure of central location cannot be...

Question 6

What is the smallest measure of central location in a positively skewed distribution? ____________.

Accepted Answer

The answer of What is the smallest measure of central...

Question 7

If a distribution is highly skewed,what measure of central location should be avoided? _____________.

Accepted Answer

The answer of If a distribution is highly skewed,what measure...

Question 8

The value that occurs most often in a set of data is called the _____.

Accepted Answer

The answer of The value that occurs most often in...

Question 9

Samples of the wires coming off the production line were tested for tensile strength.The statistical results (in PSI)were:  According to the Empirical Rule,the middle 95 percent of the wires tested between approximately what two values?

Accepted Answer

The answer of Samples of the wires coming off the...

Question 10

If the sample variance for a frequency distribution consisting of hourly wages was computed to be 10,what is the sample standard deviation?

Accepted Answer

The sample standard deviation is the square root of the sample variance. Therefore, the sample standard deviation for this frequency distribution is the square root of 10, which is approximately 3.16. Therefore, the answer is C.

Question 11

The distribution of a sample of the outside diameters of PVC gas pipes approximates a symmetrical,bell-shaped distribution.The arithmetic mean is 14.0 inches,and the standard deviation is 0.1 inches.About 68 percent of the outside diameters lie between what two amounts?

Accepted Answer

According to the empirical rule, approximately 68% of data falls within one standard deviation of the mean in a normal distribution. Since the mean is 14.0 inches and the standard deviation is 0.1 inches, one standard deviation below the mean is 13.9 inches (14.0 - 0.1) and one standard deviation above the mean is 14.1 inches (14.0 + 0.1). Therefore, about 68% of the outside diameters lie between 13.9 and 14.1 inches. Choice C is the only option that includes this range.

Question 12

A statistic computed by summing all of the values of a distribution and dividing by the number of values is called _____________.

Accepted Answer

The answer of A statistic computed by summing all of...

Question 13

What is a characteristic of a population called? __________________.

Accepted Answer

The answer of What is a characteristic of a population...

Question 14

What measure of central location uses all of the observations in its calculation? ______________.

Accepted Answer

The answer of What measure of central location uses all...

Question 15

Which measure of central location requires that the data be ranked before it is possible to determine it? _____________.

Accepted Answer

The answer of Which measure of central location requires that...

Question 16

A sample revealed that the ages of musicians playing in small local combos are 36,29,37,32,36 and 75.What is the most appropriate measure of central location to represent the ages of the musicians? ______________.

Accepted Answer

The answer of A sample revealed that the ages of...

Question 17

A population consists of all the weights of all defensive tackles on Sociable University's football team.They are: Johnson,204 pounds;Patrick,215 pounds;Junior,207 pounds;Kendron,212 pounds;Nicko,214 pounds;and Cochran,208 pounds.What is the population standard deviation (in pounds)?

Accepted Answer

The answer of A population consists of all the weights...

Question 18

If a set of observations contains an extreme value and none of the observations repeat themselves,what is the most representative measure of central location? _____________

Accepted Answer

The answer of If a set of observations contains an...

Question 19

The weekly sales from a sample of ten computer stores yielded a mean of $25,900;a median $25,000 and a mode of $24,500.What is the shape of the distribution? ___________________.

Accepted Answer

The answer of The weekly sales from a sample of...

Question 20

What is the class with the largest number of observations called? ______________

Accepted Answer

The answer of What is the class with the largest...

Quiz 3: Describing Data: Numerical Measures