Exam 3: Describing Data: Numerical Measures

A company's human resources department was interested in the average number of years that a person works before retiring. The sample of size 11 follows: What is the arithmetic mean?

A sample of the paramedical fees charged by clinics revealed these amounts: $55, $49, $50, $45, $52, and $55. What is the median charge?

According to the Empirical rule, about 95% of the observations lie within plus and minus 2.00 standard deviations.

The mean monthly income of a group of college students is $500; the standard deviation is $50. And the mean monthly income is normally distributed. Approximately, what percent of the incomes will lie between $400 and $600?

For a data set with an odd number of observations that have been sorted from smallest to largest values, where is the median located?

The mode is the value of the observation that appears most frequently.

The measure of central location with the smallest value in a positively skewed distribution is the _________.

The sum of the deviations from the mean for the set of numbers 4, 9, and 5 will equal zero.

Which measure of central location is used to determine an average annual percent increase?

According to Chebyshev's theorem, 75% of the observations lie within plus and minus 2.00 average mean deviations.

The ages of all the patients in the isolation ward of the hospital are 38, 26, 13, 41, and 22. What is the population variance?

The following are the weekly amounts of welfare payments made by the federal government to a sample of six families: $139, $136, $130, $136, $147, and $136. What is the range?

A sample revealed that the ages of a popular group of musicians are 36, 29, 37, 32, 36, and 75. What is the median age?

In the calculation of the arithmetic mean for grouped data, which value is used to represent all the values in a particular class?

When reporting descriptive statistics for a variable, why should the report include measures of location and dispersion?

A sample of five full-service gasoline stations, each carrying three grades of gasoline, was taken, and the price per liter (to the nearest cent) was recorded for each grade of gasoline, as shown in the following table. What is the median price of unleaded gas?

A company studied the commissions paid to furniture salespersons. If the standard deviation is computed, the unit of measure used would be _________.

A stockbroker placed the following order for a customer: • 50 shares of Kaiser Aluminum at $104 a share • 100 shares of GTE at $25.25 a share • 20 shares of Boston Edison at $9.125 a share What is the weighted arithmetic mean price per share?

The difference between the maximum and minimum values in a set of data is called the _______.

A bottling company offers three kinds of delivery service: instant, same day, and within five days. The profit per delivery varies according to the kind of delivery. The profit for an instant delivery is less than the other kinds because the driver has to go directly to a grocery store with a small load and return to the bottling plant. To find out what effect each type of delivery has on the profit picture, the company summarized the data in the following table based on deliveries for the previous quarter. What is the weighted mean profit per delivery?