Answer:
The margin of error of u is of 3.8.
The 99% confidence interval for the population mean u is between 27.4 minutes and 35 minutes.
Step-by-step explanation:
We have the standard deviation for the sample, which means that the t-distribution is used to solve this question.
The first step to solve this problem is finding how many degrees of freedom, we have. This is the sample size subtracted by 1. So
df = 28 - 1 = 27
99% confidence interval
Now, we have to find a value of T, which is found looking at the t table, with 27 degrees of freedom(y-axis) and a confidence level of 
. So we have T = 2.7707
The margin of error is:
In which s is the standard deviation of the sample and n is the size of the sample.
The margin of error of u is of 3.8.
The lower end of the interval is the sample mean subtracted by M. So it is 31.2 - 3.8 = 27.4 minutes
The upper end of the interval is the sample mean added to M. So it is 31.2 + 3.8 = 35 minutes
The 99% confidence interval for the population mean u is between 27.4 minutes and 35 minutes.
Answer:
b. 65
a. The notation f(-2) means that we want to evaluate the value of the equation when x = -2
Step-by-step explanation:
A. The notation f(-2) means that we want to evaluate the value of the equation when x = -2
B. We will simply substitute the value of 2 for x
f(x) = 6(8-x) + 5
f(-2) = 6(8 - (-2)) + 5
f(-2) = 6(8 + 2) + 5
f(-2) = 6(10) + 5 = 60 + 5 = 65
Answer:use a right triangle calc. On the web it does it for you and shows you how it got the answer.
Step-by-step explanation:
Answer:
You pay more for your lunch bill on Sunday
Step-by-step explanation:
You pay a total of $15.80 on Saturday and $16.27 on Sunday
Answer:
see explanation
Step-by-step explanation:
I don't have graphing facilities but can give you the vertex and 1 other point.
Given a parabola in standard form
y = ax² + bx + c ( a ≠ 0 )
Then the x- coordinate of the vertex is
x = - 
y = - x² - 2x + 8 ← is in standard form
with a = - 1 and b = - 2 , then
x = - 
= - 1
Substitute x = - 1 into the equation for corresponding value of y
y = - (- 1)² - 2(- 1) + 8 = - 1 + 2 + 8 = 9
vertex = (- 1, 9 )
To obtain another point substitute any value for x into the equation
x = 0 : y = 0 - 0 + 8 , then (0, 8 ) is a point on the graph
x = 2 : y = - (2)² - 2(2) + 8 = - 4 - 4 + 8 = 0 then (2, 0 ) is a point on the graph
