Answer:
Confidence Interval in 95% confidence level for the quality rating is (6.06,7.46)
Step-by-step explanation:
Confidence Interval can be calculated using the formula M±ME where
- M is the mean of the sample
- ME is the margin of error in a given confidence level
Using the sample obtained from 50 business travelers we get
- Mean of the sample is 6.76
- standard deviation of the sample is 2.526
Margin of error (ME) around the mean using the formula
ME=
where
- z is the corresponding statistic in 95% confidence level (1.96)
- s is the standard deviation of the sample (2.526)
- N is the sample size (50)
Using the numbers in the formula we get:
ME=
≈ 0.70
Then the confidence interval becomes 6.76±0.70
Answer:
P-value is lesser in the case when n = 500.
Step-by-step explanation:
The formula for z-test statistic can be written as
here, μ = mean
σ= standard deviation, n= sample size, x= variable.
From the relation we can clearly observe that n is directly proportional to test statistic. Thus, as the value of n increases the corresponding test statistic value also increases.
We can also observe that as the test statistic's numerical value increases it is more likely to go into rejection region or in other words its P-value decreases.
Now, for first case when our n is 50 we will have a relatively low chance of accurately representing the population compared to the case when n= 500. Therefore, the P-value will be lesser in the case when n = 500.
D. The x and y values are both negative
