Answer:
Step-by-step explanation:
We want to determine a 95% confidence interval for the mean salary of all graduates from the English department.
Number of sample, n = 400
Mean, u = $25,000
Standard deviation, s = $2,500
For a confidence level of 95%, the corresponding z value is 1.96. This is determined from the normal distribution table.
We will apply the formula
Confidence interval
= mean ± z × standard deviation/√n
It becomes
25000 ± 1.96 × 2500/√400
= 25000 ± 1.96 × 125
= 25000 ± 245
The lower end of the confidence interval is 25000 - 245 =24755
The upper end of the confidence interval is 25000 + 245 = 25245
Therefore, with 95% confidence interval, the mean salary of all graduates from the English department is between $24755 and $25245
Answer:
c. A two-tailed test should be performed since the alternative hypothesis states that the parameter is not equal to the hypothesized value.
Step-by-step explanation:
Let p1 be the average score on a final exam who texted on a regular basis during the lectures for a particular class
And p2 be the average score on a final exam who did not texted at all during the lectures for a particular class
According to the Cameron's point of interest, null and alternative hypotheses are:
p1 = p2
p1 ≠ p2
Two tailed test should be performed since the alternative hypothesis states that the parameter is not equal to the hypothesized value.
Answer:
The value of the equation
.
Step-by-step explanation:
Consider the provided equation.

We need to solve the provided equation for y.
Subtract 3x from both side.


Divide both sides by 7.


Hence, the value of the equation is
.
Answer:
The latest possible date is December, 14th.
Step-by-step explanation:
Notice that the second Friday of December is n+7, where n is the date for the first Friday of December. So, the latest the first Friday, the latest the second. As the weeks have seven days, the first Friday will be between 1st and 7th of each month. So, the latest first Friday will be 7th. Therefore, the latest second Friday will be 14th.