Answer:
The 99% confidence interval for the difference in two proportions is (0.0456, 0.1944).
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 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.
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.
Western residents:
39% out of 640, so:
[tex]p_1 = 0.39[/tex]
[tex]s_1 = \sqrt{\frac{0.39*0.61}{640}} = 0.0193[/tex]
Eastern residents:
51% out of 540, so:
[tex]p_2 = 0.51[/tex]
[tex]s_2 = \sqrt{\frac{0.51*0.49}{540}} = 0.0215[/tex]
Distribution of the difference:
[tex]p = p_2 - p_1 = 0.51 - 0.39 = 0.12[/tex]
[tex]s = \sqrt{s_2^2+s_1^2} = \sqrt{0.0215^2+0.0193^2} = 0.0289[/tex]
Confidence interval:
[tex]p \pm zs[/tex]
In which
z is the z-score that has a p-value of [tex]1 - \frac{\alpha}{2}[/tex].
99% confidence level
So [tex]\alpha = 0.01[/tex], z is the value of Z that has a p-value of [tex]1 - \frac{0.01}{2} = 0.995[/tex], so [tex]Z = 2.575[/tex].
The lower bound of the interval is:
[tex]p - zs = 0.12 - 2.575*0.0289 = 0.0456[/tex]
The upper bound of the interval is:
[tex]p + zs = 0.12 + 2.575*0.0289 = 0.1944[/tex]
The 99% confidence interval for the difference in two proportions is (0.0456, 0.1944).
Jack is going to the fair. The fair charges $10 to enter and $0.25 per ticket. How much will be spent by Jack? t = tickets 0.25 + 10 10 + 0.25t
Answer:
10 + .25t
Step-by-step explanation:
The total amount spent is equal to the amount to get in plus the cost of the tickets times the number of tickets
cost = 10 + .25t
Which of the following algebraic equations models the English sentence, a number decreased by two is equal to
four?
A W + 2 = 4
B 2 -w = 4
C W-2 = 4
D w= 2-4
Answer:
The choose C. w–2=4
I hope I helped you^_^
Answer: C
Step-by-step explanation:
QUESTION 5 - 1 POINT
An investment of $32,000 is worth $38,302 after being compounded monthly at 3%. How many years was the investment
for? (Round to the nearest whole year).
9514 1404 393
Answer:
6
Step-by-step explanation:
The compound interest formula tells you the future value of principal P invested at annual rate r compounded n times per year for t years is ...
A = P(1 +r/n)^(nt)
Solving for t, we get ...
t = log(A/P)/(n·log(1 +r/n))
Using the given values, we find t to be ...
t = log(38302/32000)/(12·log(1 +0.03/12)) ≈ 5.9997
The investment was for 6 years.
Một miếng đất hình chữ nhật có chu vi 80 mét.Nếu kéo dài thêm 8 mét nữa thì diện tích tăng thêm là 72 mét vuông.Tính chiều dài và chiều rộng hình chữ nhật ban đầu ?
Answer:
Step-by-step explanation:
(D+R) = 80:2 = 40
D = 40-R
(D+8) * R = 72X
Thay D=40-R
(40-R+8)*R = 72X
R=1.55, D=38.45
Suppose that a population begins at a size of 100 and grows continuously at a rate of 200% per year. Give the formula for calculating the size of that population after t years.
A) A = 100 + te^2
B) A = 100 + e^2t
C) A = 100e^2t
D) A = 100 + 2e^t
Answer:
D)
Step-by-step explanation: Im not so sure ok i sorry if Im wrong
Solve this inequality: x+ 4< 16
Answer:
x < 12
Step-by-step explanation:
subtract 4 from both sides:
x + 4 < 16
- 4 -4
x < 12
Answer:
x<4
Step-by-step explanation:
x+4 <16
x < 16
4
x<4
I hope this will help you
Use the discriminant to determine the number of solutions to the quadratic equation −40m2+10m−1=0
From the analysis of the discriminant, you obtain that the quadratic function has no real solutions.
In first place, you must know that the roots or solutions of a quadratic function are those values of x for which the expression is 0. This is the values of x such that y = 0. That is, f (x) = 0.
Being the quadratic function f (x)=a*x² + b*x + c, then the solution must be when: 0 =a*x² + b*x + c
The solutions of a quadratic equation can be calculated with the quadratic formula:
[tex]Solutions=\frac{-b+-\sqrt{b^{2} -4*a*c} }{2*a}[/tex]
The discriminant is the part of the quadratic formula under the square root, that is, b² - 4*a*c
The discriminant can be positive, zero or negative and this determines how many solutions (or roots) there are for the given quadratic equation.
If the discriminant:
is positive: the quadratic function has two different real solutions. equal to zero: the quadratic function has a real solution. is negative: none of the solutions are real numbers. That is, it has no real solutions.In this case, a= -40, b=10 and c= -1. Then, replacing in the discriminant expression:
discriminant= 10² -4*(-40)*(-1)
Solving:
discriminant= 100 - 160
discriminant= -60
The discriminant is negative, so the quadratic function has no real solutions.
The principal amount of money for this loan is $9,500.00. If you deposit this into an account paying 4.2% annual interest compounded monthly. How much money will be in the account after 5 years? (also called Future value).
9514 1404 393
Answer:
$11,715.65
Step-by-step explanation:
The applicable formula is ...
FV = P(1 +r/n)^(nt)
where principal P earns interest at rate r compounded n times per year for t years.
FV = $9500(1 +0.042/12)^(12·5) = $9500(1.0035^60) ≈ $11,715.65
The account will hold $11,715.65 after 5 years.
Rewrite 3.16 as a fraction (the 6 is repeating)c
[tex]3\frac{16}{99} = \dfrac{313}{99}= 3.161616161616.....[/tex]
Suppose a six-sided die is tossed 1200 times and a 6 comes up 419 times. (a) Find the empirical probability for a 6 to occur. (Enter your probability as a fraction.) (b) On the basis of a comparison of the empirical probability and the theoretical probability, do you think the die is fair or biased
Answer:
Here both probabilities are not equal.
Therefore the die is not fair and biased.
Step-by-step explanation:
Now n= 1200 times and x = 419 times.
a) Empirical Probability:
[tex]=\frac{x}{n} \\\\= \frac{419}{1200}\\ \\=0.349[/tex]
Probability = 0.349
b) Theoretical Probability:
[tex]=\frac{1}{6}[/tex]
Here both probabilities are not equal.
Therefore the die is not fair and biased.
What is the value of 2 in 9,274
Answer:
200
Step-by-step explanation:
4 is in the ones place so 4 just 4
7 is in the tens place so it is 70
2 is the hundreds place so 200
9 is in the thousands place so 9.000
what is the absolute value of -5/9
Answer:
5/9
Step-by-step explanation:
In short, the absolute value of a number turns that number into a positive value no matter what. Here is a small representation:
Negative -> Positive
Positive -> Positive
Since we are working with a negative value, it will turn positive.
Best of Luck!
Which equation does the graph of the systems of equations solve?
two linear functions intersecting at 3, negative 2
−one thirdx + 3 = x − 1
one thirdx − 3 = −x + 1
−one thirdx + 3 = −x − 1
one thirdx + 3 = x − 1
Answer:
-1/3x+3 = x-1
Step-by-step explanation:
The solution is (3,-2)
Check and see if the point solves the equation
-1/3x+3 = x-1
-1/3(3) +3 = 3-1
-1+3 = 3-1
2=2 yes
Answer:
C
Step-by-step explanation:
Jupiter orbits the sun at a rate of 8 miles per second. How far does Jupitertravel in one day? Tip: There are 86400 seconds in a day.
Answer:
Jupiter travels 691200 miles a day
Step-by-step explanation:
I just did 86400 x 8
Plz give brainliest
Write the equation in slope-intercept form. y=2(x−8)+4x
Answer:
y=6x-8
Step-by-step explanation:
y=2(x-8)+4x
y=2x+4x-8, y=6x-8
find the missing side length in the image below
Answer:
The missing side length is of 5.
Step-by-step explanation:
The sides are proportional, which means that the missing side can be found using a rule of three.
x - 10
3 - 6
Applying cross multiplication:
[tex]6x = 30[/tex]
[tex]x = \frac{30}{6} = 5[/tex]
The missing side length is of 5.
At a birthday party there were five more girls than boys. If the ratio of girls to boys was 4 to 3,
how many girls were at the party? (Make a chart to help you.)
Let number if boys be x
No of girls=x+5ATQ
[tex]\\ \sf\longmapsto \dfrac{x+5}{x}=\dfrac{4}{3}[/tex]
[tex]\\ \sf\longmapsto 3(x+5)=4x[/tex]
[tex]\\ \sf\longmapsto 3x+15=4x[/tex]
[tex]\\ \sf\longmapsto 4x-3x=15[/tex]
[tex]\\ \sf\longmapsto x=15[/tex]
Number of girls[tex]\\ \sf\longmapsto x+5=15+5=20[/tex]
Will give brainliest
mplete the equation describing how
x and y are related.
Х
0 1
2
3
4
Y -1 3 7
11 15
y = 4x + [? ]
Enter the answer that belongs in [?]
Answer:
y = 4x + -1
Step-by-step explanation:
clearly seen.
(-2x) (x-3) answer please
Answer:
−2x^2+6x
Explanation:
You just have to distribute meaning you have to multiply -2x to the equation.
-1/12 to the second power? Halp me plz
Answer:
1/144
Step-by-step explanation:
(-1/12)^2
(-1/12)*(-1/12)
1/144
The age of Paul is 1/3 that of Kennedy. In four years time the age of Paul will be the same as Kennedy present age. How old is Paul now?
Answer:
Paul is 2 and Kennedy is 6
Step-by-step explanation:
6 × 1/3 = 2
2 + 4 =6
I want to know how to solve this equation
Answer:
the last two answers are the only correct ones
Lena, Hong and David sent a total of 126 text messages over their cell phones during the weekend. David sent four times as many messages as Hong. sent six more messages than Lena. How many messages did they each send?
Step-by-step explanation:
Which is the first sincetist of world
Please help me to find this answer
Answer:
37
Step-by-step explanation:
Tan(B) = 6/8
B= arctan(3/4)=37
At a time hours after taking a tablet, the rate at which a drug is being eliminated r(t)= 50 (e^-01t - e^-0.20t)is mg/hr. Assuming that all the drug is eventually eliminated, calculate the original dose.
Answer:
2500 mg
Step-by-step explanation:
Since r(t) is the rate at which the drug is being eliminated, we integrate r(t) with t from 0 to ∞ to find the original dose of drug, m. Since all of the drug will be eliminated at time t = ∞.
Since r(t) = 50 (e^-01t - e^-0.20t)
m = ∫₀⁰⁰50 (e^-01t - e^-0.20t)
= 50∫₀⁰⁰(e^-01t - e^-0.20t)
= 50[∫₀⁰⁰e^-01t - ∫₀⁰⁰e^-0.20t]
= 50([e^-01t/-0.01]₀⁰⁰ - [e^-0.20t/-0.02]₀⁰⁰)
= 50(1/-0.01[e^-01(∞) - e^-01(0)] - {1/-0.02[e^-0.02(∞) - e^-0.02(0)]})
= 50(1/-0.01[e^-(∞) - e^-(0)] - {1/-0.02[e^-(∞) - e^-(0)]})
= 50(1/-0.01[0 - 1] - {1/-0.02[0 - 1]})
= 50(1/-0.01[- 1] - {1/-0.02[- 1]})
= 50(1/0.01 - 1/0.02)
= 50(100 - 50)
= 50(50)
= 2500 mg
Question 26 of 58
Mr. Nguyen recorded the numbers of students in his homeroom class who
participated in spirit week.
The table shows the number of students who dressed up each day.
Day
Mon Tues. Wed. Thurs. Fri. Total
Number of students 2
2
5
5
6
20
Find the mean and the median of the data set.
Determine which of these values is greater.
O A. The mean, 5, is greater than the median, 4.
OB. The mean, 5, is greater than the median, 2.
O c. The median, 6, is greater than the mean, 2.
O D. The median, 5, is greater than the mean, 4.
Answer:
D
Step-by-step explanation:
The answer is D.
The area of a parallelogram is 60 f2.
The height is 5 ft. How long is the
base?
Answer:
12 feet
BRAINLIEST, PLEASE!
Step-by-step explanation:
Area = base x height
60 = base x 5
base = 60/5
base = 12
ACD = 30, Line segment AC = x + 1, Line segment CD = 2x + 2. What is x equal to? x =
Answer:
AC+ CD = ACD
X+1 + 2X + 2 = 30
3X+3 =30
3X=30–3
3X=27
X= 27/ 3
X= 9
I'm not sure of the solution, but I solved it according to a straight line (Line segment) .
I hope I helped you^_^
what is the volume of the container
If the mean age of the managers in company is 52 years with a standard deviation of 2.5 years, what is the probability that a randomly chosen manager will be between 54.5 and 57 years old
Answer:
13.5 %
Step-by-step explanation:
For a normal distribution, the Empirical Rule states that 68% of values lie between 1 standard deviation of the mean, 95% of values lie between 2 standard deviations of the mean, and 99.7% of values lie between 3 standard deviations of the mean. Here, we can see that 54.5 is 1 standard deviation away from the mean and 57 is 2 standard deviations away. This means that we want to find the difference between 1 and 2 standard deviations from the mean (in the positive direction)
To find the difference, we can simply find (percent of values 2 standard deviations of the mean) - (percent of values 1 standard deviation from the mean) = percent of values between 1 and 2 standard deviations from the mean
= 95-68 = 27 %
Finally, this gives us the percent of values between 1 and 2 standard deviations from the mean on both sides. We want to only find the positive aspect of this, as we don't care how many values are between 49.5 and 47 years old. Because normal distributions are symmetric, or equal on both sides of the mean, we can simply divide by 2 to eliminate the half we don't want, resulting in 27/2 = 13.5
The probability that a randomly chosen manager will be between 54.5 and 57 years old is 0.8413.
Given that, average age managers = 52 years standard deviation = 2.5 years.
What is standard deviation?Standard deviation is the positive square root of the variance. Standard deviation is one of the basic methods of statistical analysis. Standard deviation is commonly abbreviated as SD and denoted by 'σ’ and it tells about the value that how much it has deviated from the mean value.
Considering the equation Z = (X−μ)/σ
Where, X is the lower or higher value, as the case may be μ is the average σ is standard deviation
Now, z1= (54.5 - 52)/2.5
= 1
z2= (57 - 52)/2.5
= 2
Now, z2-z1= 2-1
= 1
P(54.5>Z<57)= 0.8413
Therefore, the probability that a randomly chosen manager will be between 54.5 and 57 years old is 0.8413.
Learn more about the standard deviation visit:
brainly.com/question/13905583.
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