Answer:
[tex]f(x) = x^3 +5x^2-4x-20[/tex]
Step-by-step explanation:
Given
[tex]Zeros: -5,-2,2[/tex]
Required
The polynomial function
If a function has a, b and c as its zeros, the function is:
[tex]f(x) = (x - a)(x - b)(x - c)[/tex]
So, we have:
[tex]Zeros: -5,-2,2[/tex]
[tex]f(x) = (x - (-5))(x - (-2))(x - 2)[/tex]
Open the inner brackets
[tex]f(x) = (x +5)(x +2)(x - 2)[/tex]
Expand the difference of two squares
[tex]f(x) = (x +5)(x^2 - 4)[/tex]
Expand
[tex]f(x) = x^3 +5x^2-4x-20[/tex]
The CEO of a large manufacturing company is curious if there is a difference in productivity level of her warehouse employees based on the region of the country the warehouse is located. She randomly selects 35 employees who work in warehouses on the East Coast (Group 1) and 35 employees who work in warehouses in the Midwest (Group 2) and records the number of parts shipped out from each for a week.
She finds that East Coast group ships an average of 1276 parts and knows the population standard deviation to be 347.
The Midwest group ships an average of 1439 parts and knows the population standard deviation to be 298.
Using a 0.01 level of significance, test if there is a difference in productivity level. What is the test statistic?
(Round to 4 decimal places)
z =
please use excel to solve
Answer:
The test statistic is z = -2.11.
Step-by-step explanation:
Before finding the test statistic, we need to understand the central limit theorem and subtraction of normal variables.
Central Limit Theorem
The Central Limit Theorem establishes that, for a normally distributed random variable X, with mean [tex]\mu[/tex] and standard deviation [tex]\sigma[/tex], the sampling distribution of the sample means with size n can be approximated to a normal distribution with mean [tex]\mu[/tex] and standard deviation [tex]s = \frac{\sigma}{\sqrt{n}}[/tex].
For a skewed variable, the Central Limit Theorem can also be applied, as long as n is at least 30.
Subtraction between normal variables:
When two normal variables are subtracted, the mean is the difference of the means, while the standard deviation is the square root of the sum of the variances.
Group 1: Sample of 35, mean of 1276, standard deviation of 347.
This means that:
[tex]\mu_1 = 1276, s_1 = \frac{347}{\sqrt{35}} = 58.6537[/tex]
Group 2: Sample of 35, mean of 1439, standard deviation of 298.
This means that:
[tex]\mu_2 = 1439, s_2 = \frac{298}{\sqrt{35}} = 50.3712[/tex]
Test if there is a difference in productivity level.
At the null hypothesis, we test that there is no difference, that is, the subtraction is 0. So
[tex]H_0: \mu_1 - \mu_2 = 0[/tex]
At the alternate hypothesis, we test that there is difference, that is, the subtraction is different of 0. So
[tex]H_1: \mu_1 - \mu_2 \neq 0[/tex]
The test statistic is:
[tex]z = \frac{X - \mu}{s}[/tex]
In which X is the sample mean, [tex]\mu[/tex] is the value tested at the null hypothesis and s is the standard error.
0 is tested at the null hypothesis:
This means that [tex]\mu = 0[/tex]
From the two samples:
[tex]X = \mu_1 - \mu_2 = 1276 - 1439 = -163[/tex]
[tex]s = \sqrt{s_1^2+s_2^2} = \sqrt{58.6537^2+50.3712^2} = 77.3144[/tex]
Test statistic:
[tex]z = \frac{X - \mu}{s}[/tex]
[tex]z = \frac{-163 - 0}{77.3144}[/tex]
[tex]z = -2.11[/tex]
The test statistic is z = -2.11.
Find the length of the missing side
Answer:
it should be 40 in.
Step-by-step explanation:
because you have to use pythagorean theorem which is A square plus B square equals C square
Hope it helps.
Q8. How many solutions does the system of equations have?
Answer:
it would be the first answer
Step-by-step explanation:
a solution is where the lines meet, and the coorinate is (1,4)
Write the algebraic expression: 4p times the sum of 7 and 5pā
Answer:
4p(7 + 5p)
Step-by-step explanation:
4p times the sum of 7 and 5pā
4p(7 + 5p)
A sample of 300 subscribers to a particular magazine is selected from a population frame of 9,000 subscribers. If, upon examining the data, it is determined that no subscriber had been selected in the sample more than once:________.
A. the sample could not have been random
B. the sample may have been selected without replacement or with replacement
C. the sample had to have been selected without replacement
D. the sample had to have been selected with replacement
Answer:
C
Step-by-step explanation:
It is determined that no subscriber had been selected in the sample more than once the sample had to have been selected without replacement.
What is the sample?A sample is a subset of data drawn from a larger population by a researcher using a predetermined selection process. These components are referred to as sample points, sampling units, or observations.
If it is determined that no subscriber had been selected in the sample more than once, this means that each subscriber was only included once in the sample. This can only occur if the sample was selected without replacement, meaning that each subscriber was selected once and only once from the population frame.
Therefore, the correct answer is C. the sample had to have been selected without replacement.
Learn more about the sample here:
https://brainly.com/question/11045407
#SPJ6
Which graph represents the equation y=-
--*x+3?
B)
t
Answer:
The correct answer would be the 3rd graph!
Hope this helps!