Answer:
48 minutes
Step-by-step explanation:
Suppose that in 2017, 52% of U.S. households had only wireless telephone service (no landlines). Suppose that in 2021, 56% of a random sample of 100 U.S. households had only wireless telephone service.
1. Using the proportion from 2017, calculate the standard error. (Remember, in the modules this test covers, we usually use the earlier year's proportion as an estimate of this year's proportion when we are calculating the standard error.)
2. Does the data allow the use of a normal model for our calculations? Explain your reasoning.
3. In this part of the test, we'll go ahead and use a normal model, regardless of whether you got "yes" or "no" as your answer to part (b). Using a normal model, calculate the approximate 95% confidence interval for the percentage of all U.S. households in 2021 that have only wireless telephone service. Explain your reasoning.
Using proportion concepts, it is found that:
1. The standard error is of 0.05.
2. Since both [tex]np \geq 10[/tex] and [tex]n(1 - p) \geq 10[/tex], a normal model can be used.
3. The 95% confidence interval for the percentage of all U.S. households in 2021 that have only wireless telephone service is (46.27%, 65.73%).
Item 1:
The standard error for a proportion p in a sample of size n is given by:
[tex]s = \sqrt{\frac{p(1 - p)}{n}}[/tex]
For 2017, we have that:
52% of the households, hence [tex]p = 0.52[/tex]Sample of 100 households, hence [tex]n = 100[/tex]Then:
[tex]s = \sqrt{\frac{p(1 - p)}{n}}[/tex]
[tex]s = \sqrt{\frac{0.52(0.48)}{100}}[/tex]
[tex]s = 0.05[/tex]
The standard error is of 0.05.
Item 2:
The normal model can be used if: [tex]np \geq 10[/tex] and [tex]n(1 - p) \geq 10[/tex]
[tex]np = 100(0.52) = 52 \geq 10[/tex]
[tex]n(1 - p) = 100(0.48) = 48 \geq 10[/tex]
Since both [tex]np \geq 10[/tex] and [tex]n(1 - p) \geq 10[/tex], a normal model can be used.
Item 3:
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]\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]\frac{1+\alpha}{2}[/tex].
Estimate of 2021, which was of 56%, hence [tex]\pi = 0.56[/tex].
95% confidence level, hence[tex]\alpha = 0.95[/tex], z is the value of Z that has a p-value of [tex]\frac{1+0.95}{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}} = 0.56 - 1.96\sqrt{\frac{0.56(0.44)}{100}} = 0.4627[/tex]
The upper limit of this interval is:
[tex]\pi + z\sqrt{\frac{\pi(1-\pi)}{n}} = 0.56 + 1.96\sqrt{\frac{0.56(0.44)}{100}} = 0.6573[/tex]
As a percentage:
0.4627 x 100% = 46.27%
0.6573 x 100% = 65.73%
The 95% confidence interval for the percentage of all U.S. households in 2021 that have only wireless telephone service is (46.27%, 65.73%).
A similar problem is given at https://brainly.com/question/16807970
which is the quotient of 3,456 divided by 24
Answer:
144
Step-by-step explanation:
What is the upper limit if a tolerance is given as 4 3/4 plus or minus 1/64
Answer: 4 & 49/64
whole part = 4
fractional part = 49/64
===============================================
Work Shown:
U = upper limit
U = (center) + (margin of error)
U = (4 & 3/4) + (1/64)
U = (4 + 3/4) + (1/64)
U = 4 + (3/4 + 1/64)
U = 4 + (48/64 + 1/64)
U = 4 + 49/64
U = 4 & 49/64
The Lower limit is 299/8 and Upper limit is 301/8.
What is Limit?A limit is a value toward which an expression converges as one or more variables approach certain values.
Given:
Tolerances are usually in the form T ±T. T is tolerance.
In this case, your dimensions will be
4 3/4 ± 1/64
If we add the tolerance to the desired length, we get the upper limit.
Upper limit = 9 3/8 + 1/32
= 75/ 8 + 1/32
= 301/8
and, If we subtract the tolerance from the desired length, we get the lower limit.
Lower limit = 9 3/8 - 1/32
= 75/ 8 - 1/32
= 299/8
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A line passes through the points (1,4) and (3,−1).
What’s the slope of the line?
Answer:
-2 1/2
Step-by-step explanation:
Using rise/run
-1 - 4 / 3 - 1
-5 / 2
-2 1/2 or -2.5
Answer:
-2.5 or -5/2
Step-by-step explanation:
Slope = rise/run
rise = -1 - 4 = -5
run = 3 - 1 =2
so rise/run = -5/2 = -2.5
Please, if you can answer this, answer my other similar ones as well. I appreciate any help so much!
Answer:
A. corresponding angles
Step-by-step explanation:
I hope that I could help!!!!!
Need help with this please
Answer:
slope: 2y-intercept: -1Step-by-step explanation:
The slope is most easily found using two grid intersections. We know that the line crosses the grid intersection (0, -1) at the y-axis. (That is the y-intercept.) And it crosses another one at (1, 1), just above the x-axis in the first quadrant.
The slope of the line between these points can be found using the slope formula:
m = (y2 -y1)/(x2 -x1)
m = (1 -(-1))/(1 -0) = 2/1 = 2
The slope can also be found by counting the grid squares of "rise" (2) for each grid square of "run" (1) between those two points or any other convenient points on the line.
m = rise/run = 2/1 = 2
The slope of the line is 2.
__
The y-intercept is the point where the line crosses the y-axis. That point is on an unmarked grid line between y = 0 and y = -2. That is, it is halfway between the values 0 and -2, so is y = -1.
The y-intercept is (0, -1).
7. What is the relationship between the 3s in
the number 98,339?
Whiskers the cat weighs 2 and 2 over 3 kg.piglio weighs 4 kg. How many times as heavy as whiskers is piglio
Answer:1.33 kg
Step-by-step explanation:
2 2/3= 8/3
8÷3= 2.66 kg
2.66-4= 1.33 kg
Find 5(-12). Thanks I just needed help real quick
Answer:
-60 ? At least that's if you meant like
[tex]5 \times ( - 12) = - 60[/tex]
Answer:
Cannot simplify As a decimal 0.41.6 Explanation: 512 does not cancel down
Step-by-step explanation:
What is 1,000,000x75-34 divided by 4=X
X=___
Step-by-step explanation:
1,000,000x75-34/4 or (1,000,000x75-34)/4 ?????
Drag the tiles to the correct boxes to complete the pairs.
Match each power of i to its equivalent expression. 1 -1 i -i
i81
i52
i99
i66
The Matching is :
1. [tex]i^{81[/tex] = i
2. [tex]i^{52[/tex] = 1
3. [tex]i^{99[/tex] = -i
4. [tex]i^{66[/tex] = -1.
What are Complex Number?Complex numbers are the numbers that are expressed in the form of a+ib where, a,b are real numbers and 'i' is an imaginary number called “iota”. The value of i = (√-1).
Given:
1. [tex]i^{81[/tex]
= i. [tex]i^{80[/tex]
= i . (i²[tex])^{40[/tex]
= i (-1[tex])^{40[/tex]
Now, the even power of (-1) gives 1.
[tex]i^{81[/tex] = i
2. [tex]i^{52[/tex]
= 1 . (i²[tex])^{26[/tex]
Now, the even power of (-1) gives 1.
=1
3. [tex]i^{99[/tex]
= i. [tex]i^{98[/tex]
= i . (i²[tex])^{49[/tex]
= i (-1[tex])^{49[/tex]
Now, the odd power of (-1) gives -1.
[tex]i^{81[/tex] = -i
4. [tex]i^{66[/tex]
= 1 . (i²[tex])^{33[/tex]
Now, the odd power of (-1) gives -1.
= (-1)
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Can someone please help me with this problem please £8.00:25p
it a ratio problem
Step-by-step explanation:
Here we will simplify the ratio 8:25 for you and show you how we did it.
To simplify the ratio 8:25, we find the greatest common divisor of 8 and 25, and then we divide 8 and 25 by the greatest common divisor.
The greatest common divisor that you can use to simplify 8:25 is 1. Which means the answer to ratio 8:25 simplified is: 8:25
Here is the math to illustrate better:
8/1 = 8 and 25/1 = 25
Thus, 8: 25 ratio simplified is 8:25
Link to understand better - https://thepercentagecalculator.net/SimplifyRatios/Simplify-Ratio-8-25.html
In an orchard, there are 15 apple trees, 28 orange trees, and a cherry tree. What is the ratio of apple trees to orange trees?
Gupta Accessories sold merchandise to a customer on credit for $4,400, terms 3/10, n/30. The cost of the merchandise to Gupta was originally $2,500. If the customer pays 6 days after the sale occurred, what amount would be entered into the Sales Discount Dr. column in its cash receipts journal? O $132. O $75. $57. $4,400. $1,900.
Answer:
d or c but 88% sure d
Step-by-step explanation:
give me brainlest please
$5.95 marked up 80%
how to convert fraction in time
Answer:
give an example
Step-by-step explanation:
The length of a rectangle is 10 times its width. If the area of the rectangle is 52 yd2, find its approximate width.
Answer: approximate width= 5.2 yd
Step-by-step explanation:
Please Help! A bridge support is represented by the top half of an ellipse, shown in the figure to the right. The point Q, which is the center of the ellipse, is at the origin. The bridge support is 18 feet high at its center and it is 25 feet from either end of the bridge to the center. Find the equation that best describes the ellipse.
The elliptical arc of the bridge is described by the length of the given semi-major and semi minor axis.
[tex]\mathrm{The \ equation \ that \ best \ describes \ the \ ellipse \ is; }\ \displaystyle \underline{\frac{x^2}{25^2} + \frac{y^2}{18^2} = 1}[/tex]Reasons:
The given parameters of the ellipse are;
Shape of the bridge support = Top half of the ellipse
Height of the bridge support at the center = 18 feet
Distance from the bridge support from the center on either side = 25 feet
The general equation of an ellipse is presented as follows;
[tex]\displaystyle \frac{x^2}{a^2} + \frac{y^2}{b^2} = 1[/tex]
Where;
a = The semi major axis = The distance from the center to the left or right support = 25 feet
b = The semi minor axis = The height of the ellipse at the center = 18 feet
Which gives;
[tex]\displaystyle \mathrm{ \underline{The \ equation \ of \ the \ ellipse \ is; \ \frac{x^2}{25^2} + \frac{y^2}{18^2} = 1}}[/tex]
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Find the value of k so that the line passing through a pair of points has the given slope.
(1, k) and (4, 1), slope = -2
k =?
[tex]\hspace{34em}|\\ (\stackrel{x_1}{1}~,~\stackrel{y_1}{k})\qquad (\stackrel{x_2}{4}~,~\stackrel{y_2}{1}) ~\hspace{10em} \stackrel{slope}{m}\implies \cfrac{\stackrel{rise} {\stackrel{y_2}{1}-\stackrel{y1}{k}}}{\underset{run} {\underset{x_2}{4}-\underset{x_1}{1}}}~~ ~~\stackrel{\stackrel{slope}{\downarrow }}{-2} \\\\\\ \cfrac{1-k}{3}= -2\implies 1-k=-6\implies -k=-7\implies k = \cfrac{-7}{-1}\implies \boxed{k = 7}[/tex]
(b). A mathematical biologist created a model to administer medicine reaction (measured in change of blood pressure or temperature) with the model given by R=m² (C /2- m/3). where c is a positive constant and m is the amount of medicine absorbed into the blood. The sensitivity to the medication is defined to be the rate of change of reaction R with respect to the amount of medicine m absorbed in the blood. (1) Find the sensitivity, R'.
(ii) Find the amount of medicine that is being absorbed into the blood when the reaction is maximum.
(iii) Find the instantaneous rate of change of sensitivity with respect to the amount of medicine absorbed in the blood.
(iv) Find the amount of medicine that is being absorbed into the blood when the sensitivity is maximum.
[Verify your answer by MATHEMATICA and attach the printout of the commands and output
(i) If R(m) = m² (c/2 - m/3) = cm²/2 - m³/3, then differentiating with respect to m gives the sensitivity function,
R'(m) = cm - m²
In Mathematica, define a function R by
R[m_] := m^2*(c/2 - m/3)
Then you can get the derivative with either R'[m] or D[R[m], m].
(ii) Find the critical points of R, i.e. the points for which R' is zero or undefined. Since R' is a polynomial, it is defined everywhere, so we only care about the first case. We have
R'(m) = cm - m^2 = m (c - m) = 0
with solutions m = 0 or m = c.
Compute the second derivative of R :
R''(m) = c - 2m
Check the sign of R'' at each critical point:
R''(0) = c - 0 = c > 0, which indicates a minimum at m = 0R''(c) = c - 2c = -c < 0, which indicates a maximum at m = cAt the second critical point, we have a maximum value of
R(c) = c³/2 - c³/3 = c³/6
In M, we get the same result via
Maximize[R[m], m]
which should return a list like
{c^3/6, {m -> c}}
where the first element is the maximum, and the second element is a list with a rule pointing the target variable m to the critical point.
(iii) We've done this in part (ii) already while carrying out the second derivative test above,
R''(m) = c - 2m
In M, this is accomplished by R''[m] or D[R[m], {m, 2}].
(iv) We carry out the derivative test like in part (ii), but this time for R'. We have critical points when
R''(m) = c - 2m = 0
which occurs for m = c/2. The second derivative of the sensitivity function is the third derivative of R,
R'''(m) = -2
which is negative for all values of m, which means R' is in fact maximized at m = c/2. At this point of maximum sensitivity, we have
R(c/2) = c(c/2)²/2 - (c/2)³/3 = c³/8 - c³/24 = c³/12
In M, run
Maximize[R'[m], m]
on the last 5 quizzes, marco has earned a total of 21 out of 25 possible points. if he has a perfect score on the next several quizzes, exactly how many points will he need to bring up his average up to 90%
Using the mean concept, it is found that we will need 15 more points to bring up his average up to 90%.
The mean of a data-set is the sum of all observations divided by the number of observations.
In this problem:
In the first 5 observations, total of 21 out of 25 points, hence the mean for these observations is [tex]\frac{21}{25} = 0.84[/tex].In the next n observations, mean of 1.Hence, the mean is:
[tex]M = \frac{0.84(5) + n}{5 + n} = \frac{4.2 + n}{5 + n}[/tex]
We want the mean to be of 0.9, thus:
[tex]M = 0.9[/tex]
[tex]\frac{4.2 + n}{5 + n} = 0.9[/tex]
[tex]4.2 + n = 0.9n + 4.5[/tex]
[tex]0.1n = 0.3[/tex]
[tex]n = \frac{0.3}{0.1}[/tex]
[tex]n = 3[/tex]
3 more testes are need, each worth 5 points, hence, 15 more points are needed to bring up his average up to 90%.
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PLEASE HELP ME I HAVE BEEN STRUGGLING FOR THE PAST HOUR CORRECT ANSWER WILL BE MARKED BRAINLEST
Answer:
I need the question
Step-by-step explanation:
Can i have brainliest anyways? I need one more :)
Answer:
whats the question
Step-by-step explanation: or sir
Hi i need help with this
Answer:
i dont know if this helps but triangle area= 1/2 times b divided by 2
Step-by-step explanation:
i need heelp plz can anyone heelp me
Answer:
c
Step-by-step explanation:
you will need to round it down to 1,sorry if wrong this is my theory
According to the graph below, how many days did Rick's Roost lay more eggs than Hen's House?
Step-by-step explanation: i d0nt kn00w
Seven is less than the difference of a number and three. Please translate this thank youuu
Answer:
7-3 i think
Step-by-step explanation:
May i have some help please?
Answer:
yes
Step-by-step explanation:
Plzzz hurry I’ll give you brainiest
Given the line and a point on the line, what is the equation of the line in point-slope form?
A) y +60 = 2(x + 40)
B) y + 60 = 2(x - 40)
Oy - 60 = 2(x + 40)
D) y - 60 = 2(x – 40)
The function f(x)=bx^2+x-7 has a remainder of 3 when divided by (x-2), where b is a real constant.Find the value of b
Step-by-step explanation:
f(x) = bx² + x - 7
g(x) = x — 2
Remainder is 3.
Let us find the zero of g(x).
→ g(x) = 0
→ g(x) = x - 2
→ 0 = x - 2
→ x = 2
Now, as when f(x) is divided by g(x), then remainder is 3. So,
→ f(2) = 2
→ b(2)² + 2 - 7 = 2
→ 4b - 5 = 2
→ 4b = 7
→ b = 7/4
Therefore, the answer is 7/4.please help asap!:)) and show work!
Answer:
The other acute angle = 33 1/3°
Step-by-step explanation:
Hard to read the angle measure.
one acute angle = 56 2/3° x = the second acute angle
Find the other acute angles.
The two acute angles sum in a right triangle = 90°
56 2/3° + x° = 90°
x = 90 - 56 2/3
x = 89 3/3° - 56 2/3°
x = 33 1/3°
