Exam 3: Descriptive Statistics

Jessica Salas,president of Salas Products,is reviewing the warranty policy for her company's new model of automobile batteries.Life tests performed on a sample of 100 batteries indicated: (1)an average life of 75 months,(2)a standard deviation of 5 months,and (3)a bell shaped battery life distribution.Approximately 99.7% of the batteries will last between ________________.

The average starting salary for graduates at a university is $33,000 with a standard deviation of $2,000.If a histogram of the data shows that it takes on a mound shape,the empirical rule says that approximately 95% of the graduates would have a starting salary between _______.

A commuter travels many miles to work each morning.She has timed this trip 5 times during the last month.The time (in minutes)required to make this trip was 44,39,41,35,and 41.What is the mean absolute deviation for this sample data?

If the median of a distribution is greater than mean,then the distribution is skewed to the left.

Jessica Salas,president of Salas Products,is reviewing the warranty policy for her company's new model of automobile batteries.Life tests performed on a sample of 100 batteries indicated: (1)an average life of 75 months,(2)a standard deviation of 5 months,and (3)a bell shaped battery life distribution.Approximately 95% of the batteries will last between ________________.

A statistics student made the following grades on 7 tests: 76,82,92,95,79,86,and 92.What is the mode?

Liz Chapa manages a portfolio of 250 common stocks.Her staff compiled the following performance statistics for two new stocks. The coefficient of variation for Salas Products,Inc.is __________.

Kurtosis is a measure of the association between two numerical variables.

A commuter travels many miles to work each morning.She has timed this trip 5 times during the last month.The time (in minutes)required to make this trip was 34,39,41,35,and 41.The median time (in minutes)required for this trip was _______.

Average deviation is a common measure of the variability of data containing a set of numbers.

For grouped data,the midpoint of each class interval is used to represent all the values in a class interval.

A commuter travels many miles to work each morning.She has timed this trip 5 times during the last month.The time (in minutes)required to make this trip was 38,33,36,47,and 41.What is the variance for this sample data?

According to Chebyshev's Theorem,approximately how many values in a large data set will be within 2 standard deviations of the mean?

The mean life of a particular brand of light bulb is 1200 hours and the standard deviation is 50 hours.It can be concluded that at least 89% of this brand of bulbs will last between _______.

An appropriate measure of central tendency for ordinal data is the mode.

The most appropriate measure of central tendency for nominal-level data is the median.

The lowest appropriate level of measurement for the median is ordinal.

The average starting salary for graduates at a university is $33,000 with a standard deviation of $2,000.If a histogram of the data shows that it takes on a mound shape,the empirical rule says that approximately 68% of the graduates would have a starting salary between _______.

The mean life of a particular brand of light bulb is 1200 hours and the standard deviation is 75 hours.Tests show that the life of the bulb is approximately normally distributed.It can be concluded that approximately 68% of the bulbs will last between _______.

Jessica Salas,president of Salas Products,is reviewing the warranty policy for her company's new model of automobile batteries.Life tests performed on a sample of 100 batteries indicated: (1)an average life of 75 months,(2)a standard deviation of 5 months,and (3)a bell shaped battery life distribution.Approximately 68% of the batteries will last between ________________.