Retailers are always interested in determining why a custome…

Retailers are always interested in determining why a customer selected their store to make a purchase. A sporting goods retailer conducted a customer survey to determine why its customers shopped at the store. The results are shown below. What percentage of the customers responded that the merchandise was the reason they shopped at the store?    

The amount of television viewed by today’s youth is of prima…

The amount of television viewed by today’s youth is of primary concern to Parents Against Watching Television (PAWT). 300 parents of elementary school-aged children were asked to estimate the number of hours per week that their child watched television. The mean and the standard deviation for their responses were 16 and 4, respectively. PAWT constructed a stem-and-leaf display for the data that showed that the distribution of times was a bell-shaped distribution. Give an interval around the mean where you believe most (approximately 95%) of the television viewing times fell in the distribution.

Civil engineers often use the straight line equation, y hat…

Civil engineers often use the straight line equation, y hat = ax + b, to model the relationship between the mean shear strength of masonry joints and precompression stress, x.  To test this theory, a series of stress tests were performed on solid bricks arranged in triplets and joined with mortar.  The  precompression stress was varied for each triplet and the ultimate shear load just before failure (called shear strength) was recorded.  The stress results for n=7 triplet tests is shown in the accompanying table.   Give a practical interpretation of the estimate of the y-intercept of the least squares line, y hat = .987x + 1.19.

In a study of feeding behavior, zoologists recorded the numb…

In a study of feeding behavior, zoologists recorded the number of grunts of a warthog feeding by a lake in the 15 minute period following the addition of food. The data showing the weekly number of grunts and the age of the warthog (in days) are listed below. Find the value for the coefficient of determination.