High School

An automobile manufacturer claims that its jeep has a 37.8 miles/gallon (MPG) rating. An independent testing firm has tested 240 jeeps and found a mean MPG of 37.9. Assume the variance is known to be 4.41. A level of significance of 0.02 will be used.

Find the value of the test statistic. Round your answer to 2 decimal places.

Enter the value of the test statistic.

Answer :

Answer:

0.74

Step-by-step explanation:

An automobile manufacturer claims that its jeep has a 37.8 miles/gallon (MPG) rating.

Given that rating of a jeep is on an average 37.8 miles/gallon and std deviation is sq rt of 4.41

Sample size = 240

Sample mean = 37.9

Significant level = 2%

Mean difference = [tex]=37.9-37.8=0.10[/tex]

Std error of sample = [tex]\frac{s}{\sqrt{n} } =\frac{\sqrt{4.41} }{\sqrt{240} } \\=0.1356[/tex]

Test statistic = Mean diff/std error

= [tex]\frac{0.1}{0.1356}\\ =0.7378[/tex]

Test statistic = 0.74 (rounding off to two decimals)