# Population Variance

One of the important features of a camera is the battery life

as measured by the number of shots taken until the battery

needs to be recharged. The data at left contain the battery

life of 27 subcompact cameras and 15 compact cameras.

Assuming that the population variances from both types of

digital cameras are equal, is there evidence of a difference

in the mean battery life between the two types of digital

cameras at the 95% confidence level? (5 pts.)

A real estate Association in a suburban community would like to study the relationship between the size of a single-family house (as measured by number of rooms) and the selling price of the house (in thousands of dollars). Two different neighborhoods are included in the study, one on the east side of the community (=0) and the other on the west side (=1). A random sample of 20 houses was selected with the results given at left.

Q-6a. State the multiple regression equation that predicts the selling price

based on the number of rooms in the neighborhood. (5 pts.)

Q-6b. Interpret the regression coefficients. (5 pts.)

Q-6c. Predict the selling price for a house with 10 rooms that is located in a