Answer:
The 95% confidence interval for the proportion of residents who think traffic is getting worse in their community is (0.2978, 0.3630).
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].
In a survey of 802 U.S. adult drivers, 265 state that traffic is getting worse in their community.
This means that [tex]n = 802, \pi = \frac{265}{802} = 0.3304[/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}} = 0.3304 - 1.96\sqrt{\frac{0.3304*0.6669}{802}} = 0.2978[/tex]
The upper limit of this interval is:
[tex]\pi + z\sqrt{\frac{\pi(1-\pi)}{n}} = 0.3304 + 1.96\sqrt{\frac{0.3304*0.6669}{802}} = 0.3630[/tex]
The 95% confidence interval for the proportion of residents who think traffic is getting worse in their community is (0.2978, 0.3630).
25 points! Please help!
Answer:
17.5(D)
Step-by-step explanation:
So, lets see:
Every 5 minutes, Raul answers 22 questions.
The test has 77 questions.
We must figure out the time it takes to answer all 77 questions.
To do this, lets first divide the total questions by the questions answered per 5 minutes:
77 / 22
=
3.5
I got 3.5 knowing that 3x22 is 66, and half(0.5) of 22 is 11, and 11 plus 66 is 77.
So, the 3.5 is how many times he answrs 22 questions in five minutes.
To make a bit more sense, basically we have to multiply the 5 minutes by the 3.5:
3.5*5
=
17.5
We know that 3 times 5 is 15. Half(0.5) of 5 is 2.5, so 15+2.5 is 17.5.
So the answer is that for the 77 quesitons, it takes 17.5 minutes
HOPe this helps!
A circle has radius 6 cm. Suppose an arc on the circle has length 31 cm. Answer the
following:
a. The fraction of the whole circle represented by this arc is
b. The measure of the central angle defined by the arc is
degrees.
C. The area of the sector defined by the arc is
cm2. (Express answer
in terms of r or pi).
Answer:
[tex]Fraction = \frac{31}{38}[/tex]
[tex]\theta = 296.18^\circ[/tex]
[tex]Area = 29.62 \pi[/tex]
Step-by-step explanation:
Given
[tex]r = 6[/tex]--- radius
[tex]L = 31[/tex] --- arc length
Solving (a): Fraction represented by the arc
First, calculate the circumference (C)
[tex]C = 2\pi r[/tex]
So, we have:
[tex]C = 2 * 3.14 * 6[/tex]
[tex]C = 38[/tex] --- approximated
So, the fraction represented by the arc is:
[tex]Fraction = \frac{L}{C}[/tex]
[tex]Fraction = \frac{31}{38}[/tex]
Solving (b): Measure of the center angle
Using arc length formula, we have:
[tex]L = \frac{\theta}{360} * 2\pi r[/tex]
This gives
[tex]31 = \frac{\theta}{360} * 2 * 3.14 * 6[/tex]
[tex]31 = \frac{\theta}{360} * 37.68[/tex]
Make [tex]\theta[/tex] the subject
[tex]\theta = \frac{360 * 31}{37.68}[/tex]
[tex]\theta = 296.18^\circ[/tex]
Solving (c): The area of the sector
This is calculated as:
[tex]Area = \frac{\theta}{360} * \pi r^2[/tex]
So, we have:
[tex]Area = \frac{296.18}{360} * \pi * 6^2[/tex]
[tex]Area = \frac{296.18}{360} * \pi * 36[/tex]
Divide 360 and 36
[tex]Area = \frac{296.18}{10} * \pi[/tex]
[tex]Area = 29.618 * \pi\\[/tex]
[tex]Area = 29.62 \pi[/tex] --- approximated
A rectangular garden has an area of 154 square feet. If its width is 11 feet, what is its length?
Answer:
[tex]Width = 14feet[/tex]
Step-by-step explanation:
Given
[tex]Area = 154[/tex]
[tex]Width = 11[/tex]
Required
The length
Area is calculated as:
[tex]Area = Length * Width[/tex]
Make Width, the subject
[tex]Width = \frac{Area}{Length}[/tex]
So, we have:
[tex]Width = \frac{154}{11}[/tex]
[tex]Width = 14feet[/tex]
(a) 34 is 85% of what number?
Answer:
[tex]40[/tex]
hope this helps you.
Can I have the brainliest please?
can anyone help me with this pls
D should be your answer :)
csc^ 2 theta- csc^ 2 theta sec^ 2
Answer:
-csc²θ(tan²θ)
Step-by-step explanation:
csc²θ-csc²θ(sec²θ)
-csc²θ(-1+sec²θ)
-csc²θ(tan²θ)
Z OO
Which of the following statements are true? Check all that apply
The distance covered on a two hour bloyole ride depende on the bike'e rate of
speed Al 10 mph, the rider will cover 20 miles. Al 18 mph, she will cover 30
miles
A. Distance(16) = 30
B. Distance(30) = 16
C. Distance(20) = 10
D. Distance(10) = 20
Answer:
Step-by-step explanation:
A. Distance(16)= 30
Help me pleaseeee thank you
Answer:
D
Step-by-step explanation:
Time is directly proportional to the Cost. And if you use the calculator you'll still get the answer by substituting the time into 21t
Please help!!!!!!!!!!!
Answer: 4 X's on 2 1/2, 3 X's on 3, 2 X's on 3 1/2, 1 X on 4
Step-by-step explanation:
The increasing annual cost (including tuition, room, board, books and fees) to attend college ) to attend college has been widely discussed in many publications including Money magazine. The following random samples show the annual cost of attending private and public colleges. Data are in thousands of dollars.
Private Colleges
53.8 42.2 44.0 34.3 44.0
31.6 45.8 38.8 50.5 42.0
Public Colleges
20.3 22.0 28.2 15.6 24.1 28.5
22.8 25.8 18.5 25.6 14.4 21.8
Required:
a. Compute the sample mean (in thousand dollars) and sample standard deviation (in thousand dollars) for private colleges.
b. What is the point estimate (in thousand dollars) of the difference between the two population means?
Answer:
a) The sample mean is of 42.7 thousand dollars.
The standard deviation is of 6.38 thousand dollars.
b) The point estimate of the difference between the two population means is of 20.4 thousand dollars.
Step-by-step explanation:
a. Compute the sample mean (in thousand dollars) and sample standard deviation (in thousand dollars) for private colleges.
Sample mean is the sum of all values divided by the number of values. So
[tex]M = \frac{53.8 + 42.2 + 44.0 + 34.3 + 44.0 + 31.6 + 45.8 + 38.8 + 50.5 + 42.0}{10} = 42.7[/tex]
The sample mean is of 42.7 thousand dollars.
Sample standard deviation is the square root of the sum of the difference squared between each number and the mean, divided by the number of values. So
[tex]S = \sqrt{\frac{(53.8-42.7)^2 + (42.2-42.7)^2 + (44.0-42.7)^2 + (34.3-42.7)^2 + (44.0-42.7)^2 + (31.6-42.7)^2 + (45.8-42.7)^2 + (38.8-42.7)^2 + (50.5-42.7)^2 + (42.0-42.7)^2}{10}} = 6.38[/tex]
The standard deviation is of 6.38 thousand dollars.
b. What is the point estimate (in thousand dollars) of the difference between the two population means?
First, we have to find the sample mean for public colleges, and then subtract the sample mean of private colleges by the sample mean of public colleges. So, for public colleges:
[tex]M = \frac{20.3 + 22.0 + 28.2 + 15.6 + 24.1 + 28.5 + 22.8 + 25.8 + 18.5 + 25.6 + 14.4 + 21.8}{12} = 22.3[/tex]
Point estimate of the difference:
42.7 - 22.3 = 20.4
The point estimate of the difference between the two population means is of 20.4 thousand dollars.
Picture Below
(i have to make this 20 characters so I'm doing this now)
Answer:
H.
Step-by-step explanation:
16x^2 is the big square area and the -10x comes from subtracting the smaller area from the big one
Answer:
H. is the answer
hope this helps
have a good day :)
Step-by-step explanation:
Question in screenshot
Answer:
See below
Step-by-step explanation:
[tex]y = {u}^{ \frac{3}{2} } \\ \\ \therefore \: \frac{dy}{du} = \frac{3}{2} {u}^{ \frac{3}{2} - 1 } = \boxed{\frac{3}{2} {u}^{ \frac{1}{2}} } \\ \\ u = 8x + 3 \\ \\ \frac{du}{dx} = 8.1 + 0 = \boxed{8}[/tex]
A tutoring company would like to understand if most students tend to improve their grades (or not) after they use their services. They sample 220 of the students who used their service in the past year and ask them if their grades have improved or declined from the previous year. Write the null and alternative hypotheses in words.
Answer:
Null hypothesis :
Grades have not improved for a majority of students
Alternative hypothesis :
Grades have improved for a majority of students
Step-by-step explanation:
The null and alternative hypothesis for this scenario who see the null hypothesis take a midpoint between improvement and decline ; which can be expressed as ;
H0 : p = 0.5
This means that the performance of students is at a centre point where it could swing either way (decline or improve).
To test of grade has improved students, the, the proportion of f students who have proved should be greater. Which is what the test intends.
H1 : p > 0.5
Use the given information to find the minimum sample size required to estimate an unknown population mean μ.
How many students must be randomly selected to estimate the mean weekly earnings of students at one college? We want 95% confidence that the sample mean is within $4 of the population mean, and the population standard deviation is known to be $25.
Answer:
151 students must be selected.
Step-by-step explanation:
We have that to find our [tex]\alpha[/tex] level, that is the subtraction of 1 by the confidence interval divided by 2. So:
[tex]\alpha = \frac{1 - 0.95}{2} = 0.025[/tex]
Now, we have to find z in the Ztable as such z has a pvalue of [tex]1 - \alpha[/tex].
That is z with a pvalue of [tex]1 - 0.025 = 0.975[/tex], so Z = 1.96.
Now, find the margin of error M as such
[tex]M = z\frac{\sigma}{\sqrt{n}}[/tex]
In which [tex]\sigma[/tex] is the standard deviation of the population and n is the size of the sample.
The population standard deviation is known to be $25.
This means that [tex]\sigma = 25[/tex]
How many students must be randomly selected to estimate the mean weekly earnings of students at one college? Sample mean within $4 of the population mean
This is n for which M = 4. So
[tex]M = z\frac{\sigma}{\sqrt{n}}[/tex]
[tex]4 = 1.96\frac{25}{\sqrt{n}}[/tex]
[tex]4\sqrt{n} = 1.96*25[/tex]
[tex]\sqrt{n} = \frac{1.96*25}{4}[/tex]
[tex](\sqrt{n})^2 = (\frac{1.96*25}{4})^2[/tex]
[tex]n = 150.1[/tex]
Rounding up:
151 students must be selected.
Can someone help me out my math grads are bad
Answer:
First answer: 5x+8x+9+3+4
Second answer: 13x+16
WILL GIVE BRAINLIEST
Answer:110 degrees
Step-by-step explanation:
find the vertex of the graph of the following quadratic equations y= -3x^2 -12x-13
Answer:
Step-by-step explanation:
The vertex is a point. The x value is defined as x = - b / 2a where
a = -3
b = - 12
x = - -12/ 2* -3
x = 12 / - 6
x = -2
what is y when x = - 2?
y = -3(-2)^2 - 12(-2) - 13
y = -12 + 24 - 13
y = -1
Does the graph agree? It should
The equation is written as
y = -3(x + 2)^2 - 1
Which of the pairs of angles are vertical angles and thus congruent? ∠A and ∠G ∠A and ∠B ∠C and ∠F ∠D and ∠H
Answer:
∠A and ∠G is the pair of vertical angles.
Step-by-step explanation:
From the figure attached,
Two lines 'm' and 'n' are two parallel lines. These lines intersect a horizontal line 'l'.
Since, "Pair of opposite angles formed at the point of intersection are the vertical angles and equal in measure."
Therefore, Opposite angles ∠A ≅ ∠G, ∠B ≅ ∠H, ∠C ≅ ∠E and ∠D ∠F are the vertical angles.
From the given options,
∠A and ∠G is the pair representing the pair of vertical angles and thus congruent.
Answer:
∠A and ∠G
Step-by-Step Explaination:
I did it on
E
D
G
E
N
U
I
T
Y
One term of a geometric sequence is a4=135. The common ratio is r=3. Write an explicit rule for the nth term.
Answer:
[tex]a_{n} = 5 * 3^{n-1}[/tex]
Step-by-step explanation:
To find the nth term of a geometric sequence, you have the general formula:
[tex]a_{1} *r^{n-1}[/tex]
where a1 is the first term and r is the common ratio. In order to find the 4th term, we can substitute what we have(n is 4 because we are looking for the fourth term):
135 = [tex]a_{1} * 3^{4 - 1}[/tex]
135 = [tex]a_{1} * 3^3[/tex]
135 = [tex]27a_{1}[/tex]
[tex]a_{1} = 5[/tex]
Now, we can substitute the first term back in:
[tex]a_{n} = 5 * 3^{n-1}[/tex]
solve this: - 4 h = 32
Answer:
o
Step-by-step explanation:
-4h=32
h=32/-4
h=-8
stay safe healthy and happy.Answer:
h=-8
Step-by-step explanation:
-4h=32
Isolate h by dividing -4 on both sides
h=32/-4
Simplify
h=-8
If this helps please mark as brainliest
The line shown below has the equation y = 2/3x-1
The highlighted point has coordinates (-4.3).
Answer:
Step-by-step explanation:
ask cymath it will help you with any mathmatical problem
From a hot-air balloon, Meena measures a 37° angle of depression to a landmark
that's 1865 feet away, measuring horizontally. What's the balloon's vertical distance
above the ground? Round your answer to the nearest hundredth of a foot if necessary.
Answer:
The balloon is 1405.38 feet above the ground.
Step-by-step explanation:
tan 37 = opp/adj = x/1865
tan 37/1 = x/1865
1865 tan 37 = x
x=1405.378303...≈1405.38
Solve for
x. Round to the nearest tenth, if necessary.
Answer:
Step-by-step explanation:
take 18 degree as reference angle
using cos rule
cos 18=adjacent/hypotenuse
0.95=x/27
0.95*27=x
25.65=x
25.7=x
Is the function shown in the graph one-to-one?
Yes, there exists one input for every output.
No, there exists more than one input for at least one output.
Yes, there exists one output for every input.
No, there exists more than one output for at least one input.
Researchers surveyed 250 college students at one time. They were asked if they were taking any engineering classes and whether or not they felt depressed. If 75 students reported taking at least one engineering class and 15 of those students said they were depressed, what is the incidence of depression in this group
Answer:
the incidence of the depression is 1 ÷ 5
Step-by-step explanation:
Given that
There is 250 college students that are surveyed
In the case when 75 students reported for minimum ne engineering class
And, out of this 15 students would be depressed
We need to find out the incidence of the depression
So
= 15 ÷ 75
= 1 ÷ 5
Hence, the incidence of the depression is 1 ÷ 5
Express 848.41 m in millimeters
42 cubes of side 8cm are packed into a cuboid
64cm by 40cm by 24cm. How many more
cubes are needed to completely fill the cuboid?
Answer:
multiply itStep-by-step explanation:
thats it
could someone help please ??
Answer:
i think it's 0.66666666666 or 1.5
Answer:
The quotient is 1.5.
Step-by-step explanation:
Find a polynomial f(x) of degree 3 that has the following zeros. -1 (multiplicity 2), 8 Leave your answer in factored form
Answer:
Ganancia neta de la ciencia y dibujos de los gobernante en la vida de las ciudadanos y ciudadanas que ah implementado la Municipalidad de tu distrito para enfrentar la pandemia de mi corazón del gobierno estás a cargo del gobierno estás a cargo
Step-by-step explanation:
Ganancia neta de la ciencia y dibujos de los gobernante en la vida de las ciudadanos y ciudadanas que ah implementado la Municipalidad de tu distrito para enfrentar la pandemia de mi corazón del gobierno estás a cargoSuppose that the function y = f(x) is decreasing on the interval ( 5, 7). What can be said about the graph of y= -f(x)
The graph of y = -f(x) is increasing on the interval ( 5, 7) if the function y = f(x) is decreasing on the interval ( 5, 7).
What is a function?It is defined as a special type of relationship, and they have a predefined domain and range according to the function every value in the domain is related to exactly one value in the range.
It is given that:
Suppose that the function y = f(x) is decreasing on the interval ( 5, 7).
The function:
y = -f(x)
Let f(x) be:
f(x) = -aˣ
Here 'a' is the real number a > 0
f(x) is decreasing on the interval ( 5, 7).
Applying transformation:
y = -f(x)
y = aˣ
Function y is increasing on the interval ( 5, 7).
Thus, the graph of y = -f(x) is increasing on the interval ( 5, 7) if the function y = f(x) is decreasing on the interval ( 5, 7).
Learn more about the function here:
brainly.com/question/5245372
#SPJ2