The city of Laguna Beach operates two public parking lots Th

The city of Laguna Beach operates two public parking lots. The Ocean Drive parking lot can accommodate up to 125 cars and the Rio Rancho parking lot can accommodate up to 130 cars. City planners are considering increasing the size of the lots and changing the fee structure. To begin, the Planning Office would like some information on the number of cars in the lots at various times of the day. A junior planner officer is assigned the task of visiting the two lots at random times of the day and evening and counting the number of cars in the lots. The study lasted over a period of one month. Below is the number of cars in the lots for 25 visits of the Ocean Drive lot and 28 visits of the Rio Rancho lot. Assume the population standard deviations are equal.

State the decision rule for .05 significance level: H₀:?₁= ?₂H₁:?₁??₂. (Negative amounts should be indicated by a minus sign. Round your answer to 3 decimal places.)

Compute the value of the test statistic. (Negative amount should be indicated by a minus sign. Round your answer to 3 decimal places.)

Is it reasonable to conclude that there is a difference in the mean number of cars in the two lots? Use the .05 significance level.

Solution

2)

n1: Group 1 sample size = 25
n2: Group 2 sample size = 28
x1: Group 1 sample average = 86.24
x2: Group 2 sample average = 92.04
s1: Group 1 std dev = 23.43
s2: Group 2 std dev = 24.12

Difference in Means: x1 - x2 = -5.8

Standard Error of Difference of Means:  
SQRT[(s1