Answer:
Step-by-step explanation:
The formula for determining confidence interval is expressed as
Confidence interval
= mean ± z × s/ √n
Where
z is the value of the z score
s = standard deviation
n = sample size
a) The 95% confidence level has a z value of 1.96
The 99% confidence level has a z value of 2.58
Since 99% confidence level z value is greater than 95% confidence level z value, if we input it into the formula, it will result to a higher confidence interval. So changing from a 95% confidence level to a 99% confidence level would make a confidence interval wider.
b) The √15 is smaller than the √350. This means that if we make use of the formula, √350 will give a lower confidence interval than that of √15. Therefore, the confidence interval would be narrower changing from a sample size of 15 to a sample size of 350.
c) Applying the formula, a standard deviation of 15 pounds would result to a lower confidence interval than a standard deviation of 20 pounds. Therefore, the confidence interval would be wider changing from a standard deviation of 15 pounds to a standard deviation of 20 pounds.
Answer:
all real numbers greater than or equal to -1
Step-by-step explanation:
In order to solve this problem we need to know the vertex and the direction its pointing.
First we expand,
x^2-6x+8
To find the x value of the vertex we use this formula (-b/2a).
-(-6)/2(1) = 3
Now we plug 3 in the equation to get the y value,
(3)^2 - 6(3) + 8 = 9 - 18 + 8 = -1
The vertex is (3,-1)
We know the graph points up because x^2 is positive
The vertex is the lowest point, so we now know that -1 is the starting range and if the graph is pointing up, that means all values greater than -1.
This leads to our answer all real numbers greater than or equal to -1.
Answer:
a. 450 b. 10078.9097
Step-by-step explanation:
a. go with the formula W=FD
F= force
W= work done
D= distance
b. go with the formula F=mgcos(x)
M= mass
G= gravity constant (9.8)
then get to the normal formula of W=FD after getting the Force
Answer:
c = 24
Step-by-step explanation:
1/3c - 7 = 1
add 7 to both sides
1/3c = 8
now multiply 3 to both sides
c = 24
