Answer:
Step-by-step explanation:
Given that a study found that the average stopping distance of a school bus traveling 50 mph was 264 feet.
Sample taken showed the following results
Since population std deviation is known and sample size is large, z test can be used.
(Left tailed test)
Mean difference =
Std error =
Z = test statistic = mean diff/std error
=
p value = 0.00017
Since p < alpha our 0.05 we reject null hypothesis
There is evidence to show that mean is less than 264 feet
(Assumptions:
Sample are randomly drawn
Sample represents the population