Answer:
The 95%-confidence interval for the percentage of history majors at U.S. universities who knew Abraham Lincoln's first Vice President is (10.5%, 12.1%).
Step-by-step explanation:
In a sample with a number n of people surveyed with a probability of a success of [tex]\pi[/tex], and a confidence level of [tex]1-\alpha[/tex], we have the following confidence interval of proportions.
[tex]\pi \pm z\sqrt{\frac{\pi(1-\pi)}{n}}[/tex]
In which
z is the z-score that has a p-value of [tex]1 - \frac{\alpha}{2}[/tex].
6250 students, 11.3% knew Abraham Lincoln's first vice-president.
This means that [tex]n = 6250, \pi = 0.113[/tex]
95% confidence level
So [tex]\alpha = 0.05[/tex], z is the value of Z that has a p-value of [tex]1 - \frac{0.05}{2} = 0.975[/tex], so [tex]Z = 1.96[/tex].
The lower limit of this interval is:
[tex]\pi - z\sqrt{\frac{\pi(1-\pi)}{n}} = 0.113 - 1.96\sqrt{\frac{0.113*0.887}{6250}} = 0.105[/tex]
The upper limit of this interval is:
[tex]\pi + z\sqrt{\frac{\pi(1-\pi)}{n}} = 0.113 + 1.96\sqrt{\frac{0.113*0.887}{6250}} = 0.121[/tex]
As percentages:
0.105*100% = 10.5%
0.121*100% = 12.1%
The 95%-confidence interval for the percentage of history majors at U.S. universities who knew Abraham Lincoln's first Vice President is (10.5%, 12.1%).
An election ballot asks voters to select four city commissioners from a group of fourteen candidates. In how many ways can this be done ?
Based on the graph, how many distinct real number solutions does the equation x3 – 3x2 + 4 = 0 have?
Answer:
2 solutions
-1 and 2
Step-by-step explanation:
Mitch jarred 12 liters of jam 2 days. How many days does Mitch need to spend making jam if he want to jar 18 jam in all
Answer:
3 days
Step-by-step explanation:
well, in 2 days mitch can jar 12 liters of jam right? but 12 is divisible by 2. so let’s just do that to help us out later, 12 / 2 = 6
now that we have that, let’s make sure. in 1 day he can jar 6, in 2 he can jar 12.
that seems right! so now, can we add 6 to 12 to make 18? yep! how many more times do we need to add 6? 1 time. so 12 + 6 = 18. every 6 liters is 1 day. so 1 day + 1 day + 1 day (18 liters) is 3 days total!
hope this helped you!
Nina purchases a gallon of milk for $3 and some tomatoes for $2 per pound
from the grocery store. Which equation represents the relationship
between the number of poundsp of tomatoes purchased and the total
amount x Nina spent at the grocery store? *
Answer:
x = 3 + 2p (2p is 2 times p)
Jada ran 15.25 kilometers. Han ran 8,500 meters. Who ran farther?
Answer:
15.25 km =15,250 m
so Jada ran further
Answer:
Jada ran farther
Step-by-step explanation:
First, convert 8,500 to kilometers.
8,500 ÷ 1,000 = 8.5
15.25 > 8.5
Have a wonderful day!
A school has found from past records that the average scores for boys is 75 in a sample of 45 boys, and the average scores for girls is 85 in a sample of 30 girls. The population standard deviations for boys' and girls' scores were 25 and 17, respectively. The 90% confidence interval for the difference of the population means is approximately (_____, −2.022). Assume that the distributions of the scores of men and women are normally distributed. Round your answer to two decimal places.
Confidence Level Corresponding zc Value
90% confidence zc=1.645
95% confidence zc=1.96
99% confidence zc=2.576
Answer:
The 90% confidence interval for the difference of the population means is approximately (-17.98, -2.02).
Step-by-step explanation:
Before building the confidence interval, we need to understand the central limit theorem and subtraction of normal variables.
Central Limit Theorem
The Central Limit Theorem estabilishes 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.
For a proportion p in a sample of size n, the sampling distribution of the sample proportion will be approximately normal with mean [tex]\mu = p[/tex] and standard deviation [tex]s = \sqrt{\frac{p(1-p)}{n}}[/tex]
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.
Boys:
Mean of 75, sample of 45, standard deviation of 25.
This means that [tex]\mu_B = 75, s_B = \frac{25}{\sqrt{45}}[/tex]
Girls:
Mean of 85, sample of 30, standard deviation of 17.
This means that [tex]\mu_G = 85, s_G = \frac{17}{\sqrt{30}}[/tex]
Distribution of the difference of mean grades of boys and girls:
[tex]\mu = \mu_B - \mu_G = 75 - 85 = -10[/tex]
[tex]s = \sqrt{s_B^2+s_G^2} = \sqrt{(\frac{25}{\sqrt{45}})^2+(\frac{17}{\sqrt{30}})^2} = 4.85[/tex]
Confidence interval:
As stated, the critical value is [tex]z = 1.645[/tex]
The margin of error is of:
[tex]M = zs = 1.645*4.85 = 7.98[/tex]
Lower bound:
[tex]\mu - M = -10 - 7.98 = -17.98[/tex]
Upper bound:
[tex]\mu + M = -10 + 7.98 = -2.02[/tex]
The 90% confidence interval for the difference of the population means is approximately (-17.98, -2.02).
9. A shipping box is shaped like a rectangular prism. The dimensions of the box are in inches, as shown below.
(w+5) inches
(w+4) inches."
(2w) inches
Which expression describes the volume, in cubic inches, of the box?
A. 2w3 + 9w + 20
B. 243 + 182 + 402
C. 2u2 + 18w + 40
D. 2w2 + 4w+5
Given:
The dimensions of the box are (w+5) inches, (w+4) inches, (2w) inches.
To find:
The expression that describes the volume of the box.
Solution:
We know that the volume of a rectangular prism is:
[tex]V=length\times breadth \times height[/tex]
Substituting the given values, we get
[tex]V=(w+5)\times (w+4) \times 2w[/tex]
[tex]V=(w^2+5w+4w+20)2w[/tex]
[tex]V=(w^2+9w+20)2w[/tex]
Using distribution property, we get
[tex]V=(w^2)2w+(9w)2w+(20)2w[/tex]
[tex]V=2w^3+18w^2+40w[/tex]
Therefore, the volume of the box is [tex]2w^3+18w^2+40w[/tex] cubic inches.
Note: All the options are incorrect.
please help me pass please I need the most help ever is someone knows how to do these pls hmu on at ixgweeb
Answer:
tanx=b/c
sinx=b/a
cosx=c/a
Step-by-step explanation:
Answer:
REVENGE
Step-by-step explanation:
What is the vertex of x2 + 8x + 12?
Answer:
(-4,-4)
YW :))
Or you could of just looked it up cause thats what I did!!
Jonathan's preschool class has 9 girls and 6 boys. Which properties can be used to determine the percent, p, of boys in the class?
addtion
becuase when you add the number of boys and girls together you get the overall number of the class.
Answer: properties would be multiplication and the answer would be 40%
Step-by-step explanation: You can use cross multiplication to identify the answer to this.
[tex]\frac{6}{15}[/tex] --> [tex]\frac{x}{100}[/tex]
Find the volume of the pyramid. Write your answer as a fraction or mixed number.
2 ft
1 ft
2 ft
Answer:
V=lwh /3
Step-by-step explanation:
Pls help I’ll brainlest and add extra points asap
Step-by-step explanation:
1. E
2. G
3. I
4. J
5. H
6. F
7. A
8. D
9. B
10. C
The inside diameter of a randomly selected piston ring is a normally distributed random variable with mean 12 cm and standard deviation 0.04 cm. (a) What is the diameter that is exceeded by only 5% of the piston rings
Answer:
[tex]x=12.07[/tex]
Step-by-step explanation:
From the question we are told that:
Mean [tex]\=x =12cm[/tex]
Standard deviation [tex]\sigma=0.04[/tex]
Significance level [tex]\alpha=5\%=0.05[/tex]
Therefore
Confidence level [tex]95\%=0.95[/tex]
From table [tex]P(z<1.645)=0.95[/tex]
Generally the equation for Z-score is mathematically given by
[tex]z=\frac{x-\mu}{\sigma}[/tex]
[tex]x=z\sigma+\mu[/tex]
[tex]x=1.645*0.04+12[/tex]
[tex]x=12.07[/tex]
Identify all of the transformation effects on the graph of the function f(x) = x when f(x) is replaced with -f(x + 4) - 6.
A)
shifted up 6 units
B)
shifted down 6 units
shifted left 4 units
D)
shifted right 4 units
E)
reflected over x-axis
Answer: B,C E put as brainliest
Step-by-step explanation:
PLEASE HELP MEEEEEEEEE
Answer:
Step-by-step explanation:
PLEASE HELP!! Find mCFD
180°
276
307
53°
Answer:
307°
Step-by-step explanation:
CF is a diameter of the circle. so, any arc connecting C and F has an arc angle of 180° (half-circle).
so, we need to add the arc angle FD.
we know the arc angle ED = 79°.
so, what is left to add is the arc angle FE.
the arc angle FE is the same as BC.
and the arc angle BC is the supplementary angle (means together they have 180°) to 132° :
BC = 180 - 132 = 48°
therefore,
the arc angle CFD = 180 + 48 + 79 = 307°
How find the length of a hypotenuse triangle
Answer:
Step-by-step explanation:
A hypotenuse is calculated on a triangle with a right angle. The hypotenuse is the side opposite the sides with the right angle. The equation is a^2 + b^2=c^2 where the hypotenuse is the square root of c.
Is the answer yes or no?
Answer:
yes
Step-by-step explanation:
because in order to create a right triangle all of its sides must be different
Answer:
Yes
Step-by-step explanation:
Using the Pathagerum theorm (C**2 = A**2 + B**2)
The hypotinuse as always the longest side except for an equal lateral triangle. So if it is a right angle triagle so if true then,
13**2 = 5**2 + 12**2
169 = 25 + 144
169 = 169
so it is true (YES).
Alex is making a blanket for her nephew. The blanket has a length of 5 ft and a width of 4 ft. She is going to sew ribbon edging around the perimeter of the blanket. The edging costs $3 per yard. How much will it cost for Alex to get the amount of ribbon edging that she needs? Help Resa 5 ft Skip 4 ft 4 ft 5 ft HINT: There are 3 feet in one yard.
She will need 6 yards. the permiter is 16 which 5 wouldnt be enough
This is worth 30 points
Answer:
There's 3 questions which one do I answer?
Step-by-step explanation:
Find the exact value of tan 270º in simplest form with a rational denominator.
Answer:
the tangent of 270 is undefined
Step-by-step explanation:
Tan is sin/cos
270 is at (0,-1), so the cos is 0 and sin is -1
tan is -1/0 which is undefined
plz plz plz plz help me plz it is due in 1 hour and no links plz
Answer:
B
Step-by-step explanation:
The formula for the area of a triangle is given as:
A = ½*base*height
A = ½*b*h
A = (bh)2
If we know the area (A) and the base, to find the height, the following would be done:
Divide both sides by b
A/b = h/2
Multiply both sides by 2
[tex] \frac{A}{b} * 2 = h [/tex]
As we can see here, to find the base, we would divide the area by the vase, then multiply what we get by 2.
Daniel is very extraverted.He admits that he is not comfortable unless surrounded by other people,and he energetically pursues activities that require the company of others.His cousin Bill,about the same age,is very introverted.Bill is self-reflective and prefers more solitary pursuits.Regardless of their personality characteristics,which of the following is likely to contribute most to their long-term happiness?
A) They are good friends who are willing to help each other in difficult times.
B) They bought a lottery ticket together and were lucky enough to win a huge jackpot.
C) They both have jobs that require very little effort.
D) They both have very few responsibilities and are careful to avoid committing themselves to any community service.
Answer:
A is the most likely answer
Step-by-step explanation:
but how is this a math question?
plzzzzzzzz help for a brainly
Sam's first six scores were 90, 80, 90, 80, 80, and 100. What is the median of these scores?
Answer:
85
Step-by-step explanation:
17. Calculate the profit and loss percent if CP is RS 480 andSP is RS420
Answer:
there is no profit there is loss because CP is greater than SP
Step-by-step explanation:
loss=CP-SP
=Rs480-Rs420
=Rs60
loss%=loss/cp*100%
=60/480*100%
=6000/480
=12.5%
Which of the following properties is shown in the question below?
Answer:
C. Associative property of multiplication
Step-by-step explanation:
The associative property of multiplication states that the way in which factors are grouped in a multiplication problem does not change the product.
Every child who comes to Dr. Dean's dental office gets to choose a goody bag to take home.
There are 6 toothbrush colors and 8 toothpaste flavors to choose from. There are also 3
flavors of dental floss. Finally, Dr. Dean lets children choose from 5 different stickers for the
outside of the goody bag. How many different goody bags can a child make?
Answer:
720
Step-by-step explanation:
I think you just have to do
6x8x3x5
A company making tires for bikes is concerned about the exact width of their cyclocross tires. The company has a lower specification limit of 22.8 mm and an upper specification limit of 23.2 mm. The standard deviation is 0.15 mm and the mean is 23 mm. (Round your answer to 4 decimal places.) What is the process capability index for the process
Answer:
For this process, the capability index is 0.4444
Step-by-step explanation:
Given the data in the question;
Lower specification limit = 22.8 mm
Upper specification limit = 23.2 mm
The standard deviation σ = 0.15 mm
Mean μ = 23
capability index Cpk = ?
Now, Using the formula;
Cpk = min{ [(USL - μ)/3σ], [(μ - LSL)/3σ]
where USL is the Upper specification limit, LSL is the Lower specification limit, σ is the standard deviation, μ is the mean
so we substitute
Cpk = min{ [(23.2 - 23 )/(3×0.15)], [(23 - 22.8)/(3×0.15)] }
Cpk = min{ [0.2 / 0.45 ], [0.2 / 0.45] }
Cpk = min{ [ 0.4444 ], [0.4444] }
Therefore, for this process, the capability index is 0.4444
Fifty seven percent (57%) of the students applying to a university are accepted. In other words, there is a 57% probability of being accepted. A sample of 12 applicants has been selected. Using Excel, answer the questions below. Please, round your solutions to 4 decimal places (if your answer has less than 4 decimals, it is okay to leave it as it is).