Exam 3: Descriptive Statistics: Numerical Measures

In 2008, the average age of students at UTC was 22 with a standard deviation of 3.96. In 2009, the average age was 24 with a standard deviation of 4.08. In which year do the ages show a more dispersed distribution? Show your complete work and support your answer.

The frequency distribution below shows the monthly expenditure on gasoline for a sample of 14 individuals. a.Compute the mean. b.Compute the standard deviation.

Exhibit 3-3 A researcher has collected the following sample data. The mean of the sample is 5. -Refer to Exhibit 3-3. The interquartile range is

The variance can never be

A private research organization studying families in various countries reported the following data for the amount of time 4-year-old children spent alone with their fathers each day. For the above sample, determine the following measures: a.The mean b.The standard deviation c.The mode d.The 75th percentile

The standard deviation of a sample was reported to be 7. The report indicated that = 980. What has been the sample size?

Exhibit 3-1 The following data show the number of hours worked by 200 statistics students. -Refer to Exhibit 3-1. The class width for this distribution

Given the following information: Standard deviation = 8 Coefficient of variation = 64% The mean would then be

If two groups of numbers have the same mean, then

Exhibit 3-3 A researcher has collected the following sample data. The mean of the sample is 5. -Refer to Exhibit 3-3. The range is

The following is a frequency distribution of grades of a sample of statistics examinations. Compute the following measures: a.The mean b.The variance c.The standard deviation d.The coefficient of variation

From a population of size 400, a random sample of 40 items is selected. The median of the sample

In computing descriptive statistics from grouped data,

The value which has half of the observations above it and half the observations below it is called the

Which of the following symbols represents the size of the sample

Exhibit 3-4 The following is the frequency distribution for the speeds of a sample of automobiles traveling on an interstate highway. -Refer to Exhibit 3-4. The variance is

The interquartile range is used as a measure of variability to overcome what difficulty of the range?

When computing the mean, the smallest value

The numerical value of the variance

The interquartile range is