Answer:
C. Correct
Step-by-step explanation:
The interpretation of a confidence interval of x% is that we are x% that this interval contains the mean of the population.
So, for example, the interpretation of a confidence interval of 95% is that we are 95% that this interval contains the mean of the population.
In this problem, we have that:
Based on the results, a 95% confidence interval for mean number of hours worked was lower bound: 41.5 and upper bound: 45.6.
Also, the following affiration:
(A) There is a 95% chance the mean number of hours worked by adults in this country in the previous week was between 41.5 hours and 45.6 hours.
This is correct
So, the answer is:
C. Correct
Answer:
225 feet
Step-by-step explanation:
That would be 150 * 1.5
= 225 ft
Step-by-step explanation:
A study was to be undertaken to determine if a particular training program would improve physical fitness. A sample of 31 university students was selected to be enrolled in the fitness program. The researchers wished to determine if there was evidence that their sample of students differed from the general population of untrained subjects. The sample mean is 47.4 and a standard deviation of 5.3. The 98% confidence interval is determined and is given as, (45.2, 49.6) .
If the level of confidence is changed to 95%, then the confidence interval will become shorter but the p-value will not change because it is calculated using the test statistic. So the correct answer is (a).
