Exhibit 9-8
The average gasoline price of one of the major oil companies in Europe has been $1.25 per liter. Recently, the company has undertaken several efficiency measures in order to reduce prices. Management is interested in determining whether their efficiency measures have actually reduced prices. A random sample of 49 of their gas stations is selected and the average price is determined to be $1.20 per liter. Furthermore, assume that the standard deviation of the population (
) is $0.14.
Refer to Exhibit 9-8. The value of the test statistic for this hypothesis test is
◦
1.96
◦
1.645
◦
-2.5
◦
-1.645