In a survey, 250 shoppers were asked whether they have access to a computer at home and if they have a personal e-mail account.
1 answer:
You might be interested in
Answer:
a. z=3.09. Yes, it can be concluded that the population mean is greater than 50.
b. z=1.24. No, it can not be concluded that the population mean is greater than 50.
c. z=2.22. Yes, it can be concluded that the population mean is greater than 50.
Step-by-step explanation:
We have a hypothesis test for the mean, with the hypothesis:
The sample size is n=55 and the population standard deviation is 6.
The significance level is 0.05.
We can calculate the standard error as:
For a significance level of 0.05, the critical value for z is zc=1.644. If the test statistic is bigger than 1.644, the null hypothesis is rejected.
a. If the sample mean is M=52.5, the test statistic is:
The null hypothesis is rejected, as z>zc and falls in the rejection region.
b. If the sample mean is M=51, the test statistic is:
The null hypothesis failed to be rejected, as z<zc and falls in the acceptance region.
c. If the sample mean is M=51.8, the test statistic is:
The null hypothesis is rejected, as z>zc and falls in the rejection region.
Answer:
The coordinates of the point b are:
b(x₂, y₂) = (-5, -1)
Step-by-step explanation:
Given
As m is the midpoint, so
m(x, y) = m (-7, -2.5)
The other point a is given by
a(x₁, y₁) = a(-9, -4)
To determine
We need to determine the coordinates of the point b
= ?
Using the midpoint formula
substituting (x, y) = (-7, -2.5), (x₁, y₁) = (-9, -4)
Thus equvating,
Determining the x-coordinate of b
[x₂ + (-9)] / 2 = -7
x₂ + (-9) = -14
x₂ - 9 = -14
adding 9 to both sides
x₂ - 9 + 9 = -14 + 9
x₂ = -5
Determining the y-coordinate of b
[y₂ + (-4)] / 2 = -2.5
y₂ + (-4) = -2.5(2)
y₂ - 4 = -5
adding 4 to both sides
y₂ - 4 + 4 = -5 + 4
y₂ = -1
Therefore, the coordinates of the point b are:
b(x₂, y₂) = (-5, -1)