A geologist examines 18 water samples for iron concentration. The mean iron concentration for the sample data is 0.272 cc/cubic meter with a standard deviation of 0.0851. Determine the 99% confidence interval for the population mean iron concentration. Assume the population is approximately normal. Step 1 of 2: Find the critical value that should be used in constructing the confidence interval. Round your answer to three decimal places.
Answer:
The critical value that should be used in constructing the confidence interval is T = 2.898.
The 99% confidence interval for the population mean iron concentration is between 0.214 cc/cubic meter and 0.33 cc/cubic meter.
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 = 18 - 1 = 17
99% confidence interval
Now, we have to find a value of T, which is found looking at the t table, with 17 degrees of freedom(y-axis) and a confidence level of [tex]1 - \frac{1 - 0.99}{2} = 0.995[/tex]. So we have T = 2.898.
The margin of error is:
[tex]M = T\frac{s}{\sqrt{n}} = 2.898\frac{0.0851}{\sqrt{18}} = 0.058[/tex]
In which s is the standard deviation of the sample and n is the size of the sample.
The lower end of the interval is the sample mean subtracted by M. So it is 0.272 - 0.058 = 0.214 cc/cubic meter.
The upper end of the interval is the sample mean added to M. So it is 0.272 + 0.058 = 0.33 cc/cubic meter.
The 99% confidence interval for the population mean iron concentration is between 0.214 cc/cubic meter and 0.33 cc/cubic meter.
A lumber company is making boards that are 2638.0 millimeters tall. If the boards are too long they must be trimmed, and if the boards are too short they cannot be used. A sample of 18 is made, and it is found that they have a mean of 2636.5 millimeters with a standard deviation of 12.0. A level of significance of 0.05 will be used to determine if the boards are either too long or too short. Assume the population distribution is approximately normal. Is there sufficient evidence to support the claim that the boards are either too long or too short
Answer:
The answer is "Fail to reject [tex]H_o[/tex], because [tex]w_o[/tex] is sufficient evidence for claim".
Step-by-step explanation:
[tex]H_0 \mu=2638.0 \ \ / \ \ H_a \mu \neq 2638.0 \\\\\mu < 2638.0 \ \ or \ \ \mu > 2638.0 \\\\\alpha =0.05 \ \ level \ \ at \ \ sufficient \\\\[/tex]
Test Statistic:
[tex]t =\frac{\bar{x}- \mu}{\frac{S}{\sqrt{n}}}\\\\=\frac{2636.5- 2638.0}{\frac{12.0}{\sqrt{18}}}\\\\= -0.5303\\\\[/tex]
[tex]dt=17\\\\[/tex]
p-value[tex]=0.6028[/tex]
A company manufacturing computer chips finds that 8% of all chips manufactured are defective. In an effort to decrease the percentage of defective chips, management decides to provide additional training to those employees hired within the last year. After training was implemented, a sample of 450 chips revealed only 27 defects. A hypothesis test is performed to determine if the additional training was effective in lowering the defect rate. The correct value of the Z-statistic is
Answer:
The correct value of the Z-statistic is z = -1.56
Step-by-step explanation:
A company manufacturing computer chips finds that 8% of all chips manufactured are defective.
This means that the null hypothesis is:
[tex]H_{0}: p = 0.08[/tex]
A hypothesis test is performed to determine if the additional training was effective in lowering the defect rate.
This means that the alternate hypothesis is:
[tex]H_{a}: p < 0.08[/tex]
z-statistic:
[tex]z = \frac{X - \mu}{\frac{\sigma}{\sqrt{n}}}[/tex]
In which X is the sample mean, [tex]\mu[/tex] is the value tested at the null hypothesis, [tex]\sigma[/tex] is the standard deviation and n is the size of the sample.
0.08 is tested at the null hypothesis:
This means that [tex]\mu = 0.08, \sigma = \sqrt{0.08*0.92}[/tex]
After training was implemented, a sample of 450 chips revealed only 27 defects.
This means that [tex]n = 450, X = \frac{27}{450} = 0.06[/tex]
The correct value of the Z-statistic is
[tex]z = \frac{X - \mu}{\frac{\sigma}{\sqrt{n}}}[/tex]
[tex]z = \frac{0.06 - 0.08}{\frac{\sqrt{0.08*0.92}}{\sqrt{450}}}[/tex]
[tex]z = -1.56[/tex]
Easy question look at the photo
Answer:
C = 62
Step-by-step explanation:
Dad spends $227.06 at the grocery store,$95.55 at the shoe store,and $35.16 at the dry cleaners how much did dad spend in all?
Answer:
$357.77
Step-by-step explanation:
Add all of the figures together to find the answer
227.06 + 95.55 + 35.16 = 357.77
HELP PLEASE IT'S VERY IMPORTANT
Determine the area of the composite figure.
Determine the perimeter of the composite figure.
Answer:
If I did this right the perimeter is 83.7 and the area is 257.1
Explanation:
the perimeter is all sides added so 15+8+8+6.7+20+26 = 83.7
To make adding the area easier, we would separate it into different shapes.
Area of a Triangle: (b x h)/2
(15x9)/2 = 45 since it's a triangle
8x9 = 72
20x6 = 120
(6x6.7)/2 = 20.1 since it's also a triangle
45 + 72 + 120 + 20.1 = 257.1
6 dividido entre 3,978
Answer:
0.0015082956 es la respuesta pero el valor aproximado sería ≈ 0.0015083
Which choice is equivalent to the quotient below?
5. The coordinates of the points A and B are (0, 6)
and (8, 0) respectively.
() Find the equation of the line passing through
A and B
Given that the line y = x+1 cuts the line AB at
the point M, find
(ii) the coordinates of M,
(in) the equation of the line which passes
through Mand is parallel to the -axis,
(iv) the equation of the line which passes through
Mand is parallel to the y-axis.
A vehicle purchased for $29,800 depreciates at a constant rate of 4%. Determine the approximate value of
the vehicle 10 years after purchase. Round to the nearest whole dollar.
Answer:
$44104
Step-by-step explanation:
Given data
Cost = $29800
Rate= 4%
Time= 10years
Applying the formula below, we can find the cost after 10 years as
A=P(1+r)^t
A= 29800(1+0.04)^10
A=29800(1.04)^10
A=29800*1.480
A=$44104
Hence the new cost is $44104
PLEASE HELP I HAVE NO IDEA HOW TO DO SLOPES
Step-by-step explanation:
(0, 4) (4, 0)
(0-4)/(4-0) = -4/4= -1 is the slope
Can someone please help thx:)
Answer:
x = 35
Step-by-step explanation:
Angles sum of a triangle = 180
That being said we want to create an equation to solve for x
180 = 2x - 8 + x - 7 + 90 ( there is a right angle indicated by the little square; a right angle has a measure of 90 degrees, so just in case you were wondering that's where the 90 came from )
now we solve for x
step 1 combine like terms
2x + x = 3x
90 - 7 - 8 = 75
now we have 180 = 75 + 3x
step 2 subtract 75 from each side
180 - 75 = 105
75 - 75 cancels out
Now we have 105 = 3x
step 3 divide each side by 3
105 / 3 = 35
3x/3=x
we're left with x = 35
i need help with this
9514 1404 393
Answer:
26
Step-by-step explanation:
The question is asking the fraction equivalent of 0.26 (twenty-six hundredths).
That fraction is 26/100 (twenty-six hundredths). The missing number is 26.
can someone help please
13. Which equation represents y = x2 - 10x + 30 in vertex form?
y = (x - 5)2 + 5
y = (x – 5)2 + 55
y = (x – 5)2 - 5
y = (x - 5)2 + 30
Answer:
y=(x-5)2-5 it's your answer plz make me barinly least
Please guys help me please
PLEASE HELP!!
Carlos is driving to Phoenix. Suppose that the remaining distance to drive (in miles) is a linear function of his driving time (in minutes). When graphed, the function gives a line with a slope of -0.85 . See the figure below.
Carlos has 60 miles remaining after 33 minutes of driving. How many miles were remaining after 25 minutes of driving?
Answer:
See below
Step-by-step explanation:
you have to use the equation y=mx+b
We know the slope is -0.85
we can plug in -0.85 for m to give us
y=-0.85x+b
Then we can use the 60 miles and 33 minutes by plugging them in for x and y
60=-0.85*33+b (multiply the numbers)
60=-28.05+b (add 28.05 to both sides to isolate the variable)
b=88.05
Then, use b with the slope and plug in the 25 minutes for x
y=-0.85*25+88.05
y= 66.8 miles
hope this helps : D
Find the radius of circle G below.
Which value of c completes the square in the expression x2 + 14x + c?
A.-49
B.-7
C.7
D.49
If you can buy 48 plantains for $24, then how many can you buy with $4?
Answer:
Step-by-step explanation:
I believe the answer is 8 plantains. For $12 you can buy 24 plantains, for $24 you can buy 48 plantains. Now we know that it is going to be times 2. This means you could get 8 plantains.
Hope this helps!
Given that (-3,-1) is on the graph of f(x), find
the corresponding point for the function
f(x-3).
Enter the correct answer.
OOOO
DONE
Clear all
00
G2
Please awnser this for me
Answer:
B. 15 y +8 x/ 6 x y
Step-by-step explanation:
Combine the fractions by finding a common denominator.
Answer:
B
Step-by-step explanation:
A company has developed a new video game console. After completing cost analysis
and demand forecasts, the company has determined that the profit function for the
new console is p(c) = -250c^2 + 70,000c - 4,570,000, where c is the number of
consoles sold. What is the domain of the profit function?
a. all integers
b. all rational numbers
c. all integers greater than or equal to zero
d. all rational numbers greater than or equal to zero
Answer: C
Step-by-step explanation:
The domain of the profit function is (c) all integers greater than or equal to zero.
What is Function?A function is a relation from a set A to a set B where the elements in set A only maps to one and only one image in set B. No elements in set A has more than one image in set B.
Given that,
A company has developed a new video game console.
After completing cost analysis and demand forecasts, the company has determined that the profit function for the new console is,
P(c) = -250c² + 70000c - 4,570,000
where c is the number of consoles sold.
Here domain is the number of consoles sold or c.
The number of consoles cannot be negative and fractions.
So the domain does not contain all integers and all fractional numbers which are rational numbers.
So the domain is all integers greater than or equal to zero.
Hence the correct option is (c).
Learn more about Profit Functions here :
https://brainly.com/question/16505782
#SPJ2
Which expression is equivalent to:
−6x+10−16
2(3x+10−8)
−2(3x−5+8)
−2x(3−5+8)
2x(−3−10−8)
Answer:
from the given equation
Step-by-step explanation:
eqn 1 = eqn 3= eqn 4
these all are equivalent
For an art project, Jack used a piece of rope that was of a foot long. Daniel used a piece of rope that was 5 times as long. How long was Daniel's piece of rope?
Answer:
5 feet aka 60 inches
Step-by-step explanation:
A 5 feet
Multiply 12 times 5
Which is equal to 60 inches
5 feet= 60 inches
Please hurry and solve for 40 points
Answer:
x=3 y=-2
Step-by-step explanation:
Elimination would bring the equation to
3x=18
18/6 is 3
6-3y=12
-3y=6
y=-2
Find all solutions to 2sin(θ)=√3 on the interval 0≤θ<2π
Answer:
2sin(3θ) - √3 = 0
Step-by-step explanation:
sin(3θ) = √3/2
3θ = π/3 + 2kπ or 2π/3 + 2kπ, k = 0, ±1, ±2, ±3,...
θ = π/9 + 2kπ/3, 2π/9 + 2kπ/3
If k = 0, we get θ = π/9, 2π/9
If k = 1, we get θ = 7π/9, 8π/9
If k = 2, we get θ = 13π/9, 14π/9
Other values of k give values of θ lying outside of the interval [0, 2π).
We want to find all the solutions of 2sin(θ) = √3 on the interval 0 ≤ θ ≤ 2π. The only solution is θ = 1.05
So we want to solve the equation: 2sin(θ) = √3
First, we divide both sides by 2 to get:
sin(θ) = (√3)/2
Now remember the inverse sine function, it acts as follows:
Asin(sin(x)) = xsin(Asin(x)) = x
So we can apply this to both sides to get:
Asin(sin(θ)) = Asin((√3)/2)θ = Asin((√3)/2) = 1.05
And because we know that the period of the sine function is 2π, we know that there is only one solution on the range between 0 and 2π, then the only solution in the interval is:
θ = 1.05
If you want to learn more, you can read:
https://brainly.com/question/12015707
2. How many radians are in a full circle? ?
ON
ㅇ
0 27
ㅇ
Answer:
1 radius in a full circle
Answer: 6.28 radians
Step-by-step explanation: I think pls BRAINLIEST
Please help
I don't know how to salve it
Answer:
20
Step-by-step explanation:
trust me
Answer:
51.2
Step-by-step explanation:
Since it's a percentage all you have to do is multiply 32 by 1.6 because a 100 percent is equivalent to 1 so 160 percent is equivalent to 1.6.
simplify 14x(7xy^14)(-9x^-7 y^-3)
Answer:
-882y^11/x^5
Step-by-step explanation: