Exam 3: Descriptive Statistics: Numerical Methods

The local amusement park was interested in the average wait time at their most popular roller coaster at the peak park time (2 p.m. ).They selected 13 patrons and had them get in line between 2 and 3 p.m.Each was given a stopwatch to record the time they spent in line.The times recorded were as follows (in minutes;mean = 114.15): 118,124,108,116,99,120,148,118,119,121,45,130,118. What is the range?

A measure of the strength of the linear relationship between x and y that is dependent on the units in which x and y are measured.

Find the z-score for an IQ test score of 92 when the mean is 100 and the standard deviation is 15.

The local amusement park was interested in the average wait time at their most popular roller coaster at the peak park time (2 p.m. ).They selected 13 patrons and had them get in line between 2 and 3 p.m.Each was given a stopwatch to record the time they spent in line.The times recorded were as follows (in minutes). 118,124,108,116,99,120,148,118,119,121,45,130,118 What is the 65^th percentile?

The median is the measure of central tendency that divides a population or sample into four equal parts.

Using grouped data of 14 classes with a sample mean of 51 and a sample variance of 6.42,calculate the group sampled standard deviation.

The following frequency table summarizes the ages of 60 shoppers at the local grocery store. The sample mean for the above frequency table is calculated as 36.25.Calculate the approximate sample standard deviation for this data set.

In a statistics class,10 scores were randomly selected with the following results: 74,73,77,77,71,68,65,77,67,66 What is the first quartile?

As the coefficient of variation _______________,risk ______________.

The average of the squared deviations of the individual population measurement from the population mean is the ___________.

The weights that are used in calculating a weighted mean will vary depending on the situation.

The population mean is the point estimate of the sample mean.

Researchers wish to study fuel consumption rates based on speed.The data from the test car at 10 speeds are below. It can be shown that for these data: Calculate the sample correlation coefficient.

Suppose that annual sales for a company were $3.6 million at the beginning of a three-year period and at the end had increased to $6.1 million.Find the geometric growth rate of sales.

In a statistics class,10 scores were randomly selected with the following results: 74,73,77,77,71,68,65,77,67,66 What is the third quartile?

In a study of the factors that affect success in economics,data were collected for 8 business students.Scores on a calculus placement test are given with economics final exam scores.The data are below: It can be shown that for these data: 140.75. Calculate the sample covariance.

An initial investment of $10,000 is observed over 3 years with a geometric mean return at the end of year 3 of 0.512.Determine the value of the investment after 3 years.

Quality control is an important issue at ACME Company,which manufactures light bulbs.To test the life-hours of their light bulbs,they randomly sampled nine light bulbs and measured how many hours they lasted: 378,361,350,375,200,391,375,368,321. What is the median?

If a population distribution is skewed to the right,then,given a random sample from that population,one would expect that the ____________.

In the least squares line,___________ is defined as rise/run.