A researcher wishes to estimate the number of households with two cars. A previous study indicates that the proportion of households with two cars is 25%. How large a sample is needed in order to be 99% confident that the sample proportion will not differ from the true proportion by more than 3%?
A) 4.
B) 1132.
C) 1842.
D) 1382.

Hey there! I'm happy to help!

Let's set this up a proportion (two equal ratios) to find out how many miles Wina can drive on 12 gallons gas.

[tex]\frac{miles}{gallons} =\frac{282}{10} =\frac{m}{12}[/tex]

What do we multiply the bottom 10 by to get to 12? Well, to find out, we can divide 12 by 10 below.

12÷10=1.2

This means that we multiply the numbers in the first fraction by 1.2 to have the same numerator and denominator as the second fraction.

If we multiplied our 10 b y 1.2 to get the denominator in the second fraction, we should be able to multiply 282 by 1.2 to get the numerator in the second fraction!

282×1.2=338.4

If you use 338.4 in this proportion, the ratios will be equal.

Therefore, Wina could drive 338.4 miles on 12 miles of gas at this same rate.

Have a wonderful day!

Answer:

work is shown and pictured

Hi there! Hopefully this helps!

--------------------------------------------------------------------------------------------------             The frequency is ~7.5*1014 Hz

Since visible light has a wavelength spectrum of ~400 nm to ~700 nm, Violet light has a wavelength of ~400 nm and a frequency of ~7.5*1014 Hz.

Step-by-step explanation:

Speed = wavelength × frequency

3×10⁸ m/s = (400×10⁻⁹ m) f

f = 7.5×10¹⁴

Answer:

4/ 100000

hope it was useful for you

stay at home stay safe

pls mark me as brain.....m

keep rocking

Answer:

The graphs for the lines of the costs are in the attachment. For this answer you have to first determine the equations for each cost. Since Hammy's Froyo charges $2.40 for the container and $.40 for each ounce, the equation would be y=.40x+2.40. For Yogurt Palace, which charges $0.80 for each ounce, the equation would be y=.80x.

Answer:

twenty one balls.

Step-by-step explanation:

there would be three of each colour.

Answer:

the real answer is 15

Step-by-step explanation:

You want to end up with [tex]A\sin(\omega t+\phi)[/tex]. Expand this using the angle sum identity for sine:

[tex]A\sin(\omega t+\phi)=A\sin(\omega t)\cos\phi+A\cos(\omega t)\sin\phi[/tex]

We want this to line up with [tex]2\sin(4\pi t)+5\cos(4\pi t)[/tex]. Right away, we know [tex]\omega=4\pi[/tex].

We also need to have

[tex]\begin{cases}A\cos\phi=2\\A\sin\phi=5\end{cases}[/tex]

Recall that [tex]\sin^2x+\cos^2x=1[/tex] for all [tex]x[/tex]; this means

[tex](A\cos\phi)^2+(A\sin\phi)^2=2^2+5^2\implies A^2=29\implies A=\sqrt{29}[/tex]

Then

[tex]\begin{cases}\cos\phi=\frac2{\sqrt{29}}\\\sin\phi=\frac5{\sqrt{29}}\end{cases}\implies\tan\phi=\dfrac{\sin\phi}{\cos\phi}=\dfrac52\implies\phi=\tan^{-1}\left(\dfrac52\right)[/tex]

So we end up with

[tex]2\sin(4\pi t)+5\cos(4\pi t)=\sqrt{29}\sin\left(4\pi t+\tan^{-1}\left(\dfrac52\right)\right)[/tex]

Answer:

Step-by-step explanation:

In the form ...

  y(t) = Asin(ωt +φ)

you have ...

The translation from ...

  y(t) = 2sin(4πt) +5cos(4πt)

is ...

  A = √(2² +5²) = √29 . . . . the amplitude

  ω = 4π . . . . the angular frequency in radians per second

  φ = arctan(5/2) ≈ 1.1903 . . . . radians phase shift

Then, ...

  y(t) = √29·sin(4πt +1.1903)

_____

Comment on the conversion

You will notice we used "2" and "5" to find the amplitude and phase shift. In the generic case, these are "coefficient of sin( )" and "coefficient of cos( )". When determining phase shift, pay attention to whether your calculator is giving you degrees or radians. (Set the mode to what you want.)

If you have a negative coefficient for sin( ), you will need to add 180° (π radians) to the phase shift value given by the arctan( ) function.

Answer:

0.078

Step-by-step explanation:

The probability P(A) of an event A happening is given by;

P(A) = [tex]\frac{number-of-possible-outcomes-of-event-A}{total-number-of-sample-space}[/tex]

From the question;

There are two events;

(i) Drawing a first card which is a king: Let the event be X. The probability is given by;

P(X) = [tex]\frac{number-of-possible-outcomes-of-event-X}{total-number-of-sample-space}[/tex]

Since there are 4 king cards in the pack, the number of possible outcomes of event X = 4.

Also, the total number of sample space = 52, since there are 52 cards in total.

P(X) = [tex]\frac{4}{52}[/tex] = [tex]\frac{1}{13}[/tex]

(ii) Drawing a second card which is a queen: Let the event be Y. The probability is given by;

P(Y) = [tex]\frac{number-of-possible-outcomes-of-event-Y}{total-number-of-sample-space}[/tex]

Since there are 4 queen cards in the pack, the number of possible outcomes of event Y = 4

But then, the total number of sample = 51, since there 52 cards in total and a king card has been removed without replacement.

P(Y) = [tex]\frac{4}{51}[/tex]

Therefore, the probability of selecting a first card as king and a second card as queen is;

P(X and Y) = P(X) x P(Y)

= [tex]\frac{1}{13} * \frac{4}{51}[/tex] = 0.078

Therefore the probability is 0.078

Answer:

108 degrees

Step-by-step explanation:

angle CDE is 108 degrees, which is supplementary to angle EDH, so EDH must be 72 degrees

then put it into an equation

90+90+72+x=360

solve

x=108

Answer:

The answer is 108

Answer:

((23GM)

Step-by-step explanation:

it goes for this because 23gm = 40pm

Answer:

A) P(A|B) = 0.01966

B) P(A'|B') = 0.99944

Step-by-step explanation:

A) We are told that A is the event "the person is infected" and B is the event "the person tests positive".

Thus, using bayes theorem, the probability that the person is infected is; P(A|B)

From bayes theorem,

P(A|B) = [P(A) × P(B|A)]/[(P(A) x P(B|A)) + (P(A') x P(B|A'))]

Now, from the question,

P(A) = 1/400

P(A') = 399/400

P(B|A) = 0.8

P(B|A') = 0.1

Thus;

P(A|B) = [(1/400) × 0.8)]/[((1/400) x 0.8) + ((399/400) x (0.1))]

P(A|B) = 0.01966

B) we want to find the probability that when a person tests negative, the person is not infected. This is;

P(A'|B') = P(Not infected|negative) = P(not infected and negative) / P(negative) = [(399/400) × 0.9)]/[((399/400) x 0.9) + ((1/400) x (0.2))] = 0.99944

Answer:

Barts total cost is (c)213.36

Step-by-step explanation:

First, you subtract 6% from $219

=204.92

add shipping,

+7.50

=213.36

Hope this helps <3

Answer:

C. $213.36

Step-by-step explanation:

The original price is $219 and the discount is 6% which is equal to $13.14

$219 - $13.14 + $7.50 (shipping cost) = $213.36

Answer:

The system has exactly one solution where x = 0 and y = -3.

Step-by-step explanation:

-6x + y = -3

7x - y = 3

(7x - 6x) + (y - y) = 3 - 3

x + 0 = 0

x = 0

7(0) - y = 3

0 - y = 3

-y = 3

y = -3

-6(0) + y = -3

0 + y = -3

y = -3

So, the system has exactly one solution where x = 0 and y = -3.

Hope this helps!

Answer:

Option C.

Step-by-step explanation:

We have to see the common things we have in both graphs and express them:

1. There is a value x=a≠0, where g(a)=f(a)=0

2. The slope of g(x) is of opposite sign of the slope of f(x). Then f(x)=m*g(cx) with m<0.

3. The slope of f(x) seems to be higher than the slope of g(x)

A. As the slopes are different, this is not adequate.

B. As the slopes are different, this is not adequate.

C. This can be adequate, as it applies to all the observations we have made.

D. This is not adequate because f(0)≠g(-2*0).

The only adequate option then is C.

Answer:

I=0.24ampere

Step-by-step explanation:

Assuming that the voltage is the same:

I=V/R (V- voltage, I-current, R-resistance)

1/6ampere=V/3240ohms

V=1/6*3240

= 5400v

Voltage across =V=5400v

Since the voltage is the same when the resistance is 22500ohms

I=V/R

=5400/22500

=6/25

=0.24ampere

Answer:

  a) -900 L/min

  b) 63000 L

  c) v = -900t +63000

  d) 7200 L

Step-by-step explanation:

a) You are given two points on the curve of volume vs. time:

  (t, v) = (20, 45000) and (70, 0)

The rate of change is ...

  Δv/Δt = (0 -45000)/(70 -20) = -45000/50 = -900 . . . . liters per minute

__

b) In the first 20 minutes, the change in volume was ...

  (20 min)(-900 L/min) = -18000 L

So, the initial volume was ...

  initial volume -18000 = 45000

  initial volume = 63,000 . . . . liters

__

c) Since we have the slope and the intercept, we can write the equation in slope-intercept form:

  v = -900t +63000

__

d) Put the number in the equation and do the arithmetic.

When t=62, the amount remaining is ...

  v = -900(62) +63000 = -55800 +63000 = 7200

7200 L remain after 62 minutes.

Answer:

Step-by-step explanation:

Let

T = number of trees

A = number of acorns

Given:

A =  18T + 4 ...........................(1)

A = 20T -4 .........................(2)

Equate A from (1) and (2)

20T-4 = 18T+4

simplify and solve for T

20T - 18T = 4+4

2T = 8

T = 4 trees

A = 18T + 4 = 72+4 = 76 acorns, or

A = 20T - 4 = 80 - 4 = 76 acorns.

Answer: 77 degrees

Step-by-step explanation:

interior angles on the same side of transversal are supplementary.  Thus,

103+x=180

x = 77

Hope it helps <3

Answer:

Hey there!

This is a parallelogram, and we have the angles next to each  other add to 180 degrees. Angle ABC+Angle BCD=180

103+x=180

x=77

BCD=77 degrees.

Let me know if this helps :)

Answer:

B

Step-by-step explanation:

Answer:

The answer for this Question is Elementary

It is B.

Answer:

-1.946 ; C

Step-by-step explanation:

Here, we want to identify the value of the z-statistic

Mathematically;

z = (x -mean)/SD/√n

Thus we have ;

Z = (11.58-12)/1.93/√80

z = -1.946

Answer:

the dimensions that will minimize the cost of constructing the box is:

a = 5.8481  in ;   b = 5.848 in  ; c = 10.234 in

Step-by-step explanation:

From the information given :

Let a be the base if the rectangular box

b to be the height and c to be the  other side of the rectangular box.

Then ;

the area of the base is ac

area for the front of the box is ab

area for the remaining other sides   ab + 2cb

The base of the box is made from a material costing 8 ac

The front of the box must be decorated, and will cost 10 ab

The remainder of the sides will cost 4 (ab + 2cb)

Thus ; the total cost  C is:

C = 8 ac + 10 ab + 4(ab + 2cb)

C = 8 ac + 10 ab + 4ab + 8cb

C = 8 ac + 14 ab + 8cb   ---- (1)

However; the volume of the rectangular box is V = abc = 350 in³

If abc = 350

Then b = [tex]\dfrac{350}{ac}[/tex]

replacing the value for c in the above equation (1); we have :

[tex]C = 8 ac + 14 a(\dfrac{350}{ac}) + 8c(\dfrac{350}{ac})[/tex]

[tex]C = 8 ac + \dfrac{4900}{c}+\dfrac{2800}{a}[/tex]

Differentiating C with respect to a and c; we have:

[tex]C_a = 8c - \dfrac{2800}{a^2}[/tex]

[tex]C_c = 8a - \dfrac{4900}{c^2}[/tex]

[tex]8c - \dfrac{2800}{a^2}=0[/tex] --- (2)

[tex]8a - \dfrac{4900}{c^2}=0[/tex]   ---(3)

From (2)

[tex]8c =\dfrac{2800}{a^2}[/tex]

[tex]c =\dfrac{2800}{8a^2}[/tex] ----- (4)

From (3)

[tex]8a =\dfrac{4900}{c^2}[/tex]

[tex]a =\dfrac{4900}{8c^2}[/tex]   -----(5)

Replacing the value of a in 5 into equation (4)

[tex]c = \dfrac{2800}{8*(\dfrac{4900}{8c^2})^2} \\ \\ \\ c = \dfrac{2800}{\dfrac{8*24010000}{64c^4}} \\ \\ \\ c = \dfrac{2800}{\dfrac{24010000}{8c^4}} \\ \\ \\ c = \dfrac{2800*8c^4}{24010000} \\ \\ c = 0.000933c^4 \\ \\ \dfrac{c}{c^4}= 0.000933 \\ \\ \dfrac{1}{c^3} = 0.000933 \\ \\ \dfrac{1}{0.000933} = c^3 \\ \\ 1071.81 = c^3\\ \\ c= \sqrt[3]{1071.81} \\ \\ c = 10.234[/tex]

From (5)

[tex]a =\dfrac{4900}{8c^2}[/tex]   -----(5)

[tex]a =\dfrac{4900}{8* 10.234^2}[/tex]

a = 5.8481

Recall that :

b = [tex]\dfrac{350}{ac}[/tex]

b = [tex]\dfrac{350}{5.8481*10.234}[/tex]

b =5.848

Therefore ; the dimensions that will minimize the cost of constructing the box is:

a = 5.8481  in ;   b = 5.848 in  ; c = 10.234 in

The dimensions that will minimize the cost of constructing this box are: a = 5.8481 inches, b = 5.848 inches, and c = 10.234 inches and this can be determined by using the given data.

Given :

According to the given data the total cost is given by:

C = 8ac + 14ab + 8cb   --- (1)

The volume of the rectangular box is (V = abc = 350 inch cube). So, the value of b is given by:

[tex]\rm b = \dfrac{350}{ac}[/tex]

Now, substitute the value of 'b' in the equation (1).

[tex]\rm C = 8ac + \dfrac{4900}{c}+\dfrac{2800}{a}[/tex]

First differentiating the above equation with respect to c.

[tex]\rm C_c = 8a-\dfrac{4900}{c^2}[/tex]   --- (2)

Now, differentiating the above equation with respect to a.

[tex]\rm C_a = 8c-\dfrac{2800}{a^2}[/tex]    --- (3)

Now, equate equation (2) and equation (3) to zero.

From equation (2):  

[tex]\rm a=\dfrac{4900}{8c^2}[/tex]    ----- (4)

From equation (3):

[tex]\rm c=\dfrac{2800}{8a^2}[/tex]   ----- (5)

Now, from equations (4) and (5).

[tex]\rm c = \dfrac{2800}{8\left(\dfrac{4900}{8c^2}\right)^2}[/tex]

Now, simplifying the above expression in order to get the value of c.

c = 10.234

Now, put the value of 'c' in equation (5) in order to get the value of 'a'.

a = 5.8481

The value of 'b' is given by:

[tex]\rm b = \dfrac{350}{5.8481\times 10.234}[/tex]

b = 5.848

So, the dimensions that will minimize the cost of constructing this box are: a = 5.8481 inches, b = 5.848 inches, and c = 10.234 inches.

For more information, refer to the link given below:

https://brainly.com/question/19770987

Answer:

4.5 ×1000 =4500m

Step-by-step explanation:

450/1000=0.45km

Answer: 10 : 1

Step-by-step explanation: Now first let’s convert this to the same units, for instance, the SI unit for length meters. 4.5 x 1000 = 4500m. Then put the ratio 4500m : 450m. You can divide 4500 by 450 as it is divisible so you get 10 as the answer.

Even if you have converted them to kilometers before, nevermind, still 4.5 divide by 0.45 is 10 and there the answer is 10 : 1 or shortly the ratio is just 10.

Answer:

The upper confidence bound for population mean escape time is: 379.27

The upper prediction bound for the escape time of a single additional worker  is 413.64

Step-by-step explanation:

Given that :

sample size n = 26

sample mean [tex]\bar x[/tex] =  371.08

standard deviation [tex]\sigma[/tex] = 24.45

The objective is to calculate an upper confidence bound for population mean escape time using a confidence level of 95%

We need to determine the standard error of these given data first;

So,

Standard Error S.E = [tex]\dfrac{\sigma }{\sqrt{n}}[/tex]

Standard Error S.E = [tex]\dfrac{24.45 }{\sqrt{26}}[/tex]

Standard Error S.E = [tex]\dfrac{24.45 }{4.898979486}[/tex]

Standard Error S.E = 4.7950

However;

Degree of freedom df= n - 1

Degree of freedom df= 26 - 1

Degree of freedom df= 25

At confidence level of 95% and Degree of freedom df of  25 ;

t-value = 1.7080

Similarly;

The Margin of error = t-value × S.E

The Margin of error = 1.7080 × 4.7950

The Margin of error = 8.18986

The upper confidence bound for population mean escape time is = Sample Mean + Margin   of  Error

The upper confidence bound for population mean escape time is =  371.08 +  8.18986

The upper confidence bound for population mean escape time is = 379.26986  [tex]\approx[/tex] 379.27

The upper confidence bound for population mean escape time is: 379.27

b.  Calculate an upper prediction bound for the escape time of a single additional worker using a prediction level of 95%.

The standard error of the mean = [tex]\sigma \times \sqrt{1+ \dfrac{1}{n}}[/tex]

The standard error of the mean = [tex]24.45 \times \sqrt{1+ \dfrac{1}{26}}[/tex]

The standard error of the mean = [tex]24.45 \times \sqrt{1+0.03846153846}[/tex]

The standard error of the mean = [tex]24.45 \times \sqrt{1.03846153846}[/tex]

The standard error of the mean = [tex]24.45 \times 1.019049331[/tex]

The standard error of the mean = 24.91575614

Recall that : At confidence level of 95% and Degree of freedom df of  25 ;

t-value = 1.7080

∴

The Margin of error = t-value × S.E

The Margin of error = 1.7080 × 24.91575614

The Margin of error = 42.55611149

The upper prediction bound for the escape time of a single additional worker  is calculate by the addition of

Sample Mean + Margin of Error

= 371.08 + 42.55611149

= 413.6361115

[tex]\approx[/tex] 413.64

The upper prediction bound for the escape time of a single additional worker  is 413.64

There is only one distinct triangle possible, with m N= 33º. Therefore, option B is the correct answer.

Law of Sines In trigonometry, the law of sines, sine law, sine formula, or sine rule is an equation relating the lengths of the sides of any triangle to the sines of its angles.

The formula for sine rule is sinA/a=sinB/b=sinC/c

Given that, in ΔMNO, m = 20, n = 14, and m∠M = 51°.

Now, sin51°/20=sinN/14

0.7771/20=sinN/14

0.038855=sinN/14

sinN=14×0.038855

sinN=0.54397

N=33°

Therefore, option B is the correct answer.

Learn more about the sine rule here:

https://brainly.com/question/22288720.

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Answer:

24 ways.

Step-by-step explanation:

In this case, you just need a factorial.

For the first seat, you have 4 students you can place.

For the second seat, you have 3 students.

For the third, you have 2.

For the fourth, you have 1.

So, you can arrange the students by doing 4 * 3 * 2 * 1 = 12 * 2 = 24 ways.

Hope this helps!

Answer:

Explantation:

First seat: 4 seats

Second seat: 3 seats

Third: 2 seats

Fourth seat: 1 seat remaining

4 * 3 * 2 * 1 = 12 * 2 * 1 = 24 * 1 = 24

Answer:

72mile/hr

Step-by-step explanation:

Let d be distance in mile

Let r be average rate in mile/hr

Let t be time in hr

d = r × t

t = d/r

360/r = t ........1

Also

The question stated that the average speed was 6 less to travel a distance of 330mile at the same time.

Since the average speed is r, hence 6 less that r = r-6 at the same time

Therefore

330/r-6 = same time ( t ) .......2

Equate 1 and 2

360/r = 330/r-6

Cross multiply

360(r-6) = 330(r)

360r - 360×6 = 330r

360r - 2160 = 330r

Collecting like terms

- 2160 = 330r - 360r

- 2160 = - 30r

Divide both sides by - 30

- 2160/ - 30 = - 30r/ - 30

r = 72mile/hr

Hence the average speed is 72mile/hr

Answer: cross-sectional study

Step-by-step explanation:

Here, A research company uses a device to record the viewing habits of about 2500 ​households (that includes different persons such as adults , children and seniors )

The data collected today(at a single point in time).

If it is used to determine the proportion of households tuned to a particular children's children's program.

The type of observational study is described in the problem​ statement : "cross-sectional"

Answer:

Step-by-step explanation:

The mean value theorem for integrals for the function f(c) over a given interval [a, b] is expressed as g prime(c) = g(b) - g(a)/b-a. The idea is that there is a value c in between the interval [a, b] for the function given.

Given the function g(x) = 5√x within the interval [4,9]

g prime (c) = g(9) - g(4)/9-4

g(9) = 5√9

g(9) = 5*3 = 15

g(4) = 5√4

g(4) = 5*2 = 10

g prime c) = 15-10/9-4

g prime (c) = 5/5

g prime(c) = 1

So we are to find the number for which g prime (x) = g prime(c)

If g(x) = 5√x = [tex]5x^{1/2}[/tex]

g prime (x) = [tex]5/2 \ x^{-1/2}[/tex]

g prime (x) = 5/2√x

Since g prime (c) = 1 then;

5/2√x = 1

5 = 2√x

√x = 5/2

x = (5/2)²

x = 25/4

The value of c guaranteed by the mid value theorem is 25/4

The possible value of c for [tex]\mathbf{f(x) = 5\sqrt x\ [4,9]}[/tex] is 6.25

The function is given as:

[tex]\mathbf{f(x) = 5\sqrt x\ [4,9]}[/tex]

Calculate f(4) and f(9)

[tex]\mathbf{f(4) = 5\sqrt 4 = 10}[/tex]

[tex]\mathbf{f(9) = 5\sqrt 9 = 15}[/tex]

Substitute c for x in f(x)

[tex]\mathbf{f(c) = 5\sqrt c }[/tex]

Calculate f'(c)

[tex]\mathbf{f'(c) = \frac{f(b) - f(a)}{b - a}}[/tex]

So, we have:

[tex]\mathbf{f'(c) = \frac{f(9) - f(4)}{9 - 4}}[/tex]

[tex]\mathbf{f'(c) = \frac{f(9) - f(4)}{5}}[/tex]

This gives

[tex]\mathbf{f'(c) = \frac{15 -10 }{5}}[/tex]

[tex]\mathbf{f'(c) = \frac{5 }{5}}[/tex]

[tex]\mathbf{f'(c) = 1}[/tex]

Also, we have:

[tex]\mathbf{f'(x) = \frac 52x^{-1/2}}[/tex]

Substitute c for x

[tex]\mathbf{f'(c) = \frac 52c^{-1/2}}[/tex]

Substitute 1 for f'(c)

[tex]\mathbf{\frac 52c^{-1/2} = 1}[/tex]

Multiply through by 2/5

[tex]\mathbf{c^{-1/2} = \frac 25}[/tex]

This gives

[tex]\mathbf{c^{1/2} = \frac 52}[/tex]

Square both sides

[tex]\mathbf{c = \frac{25}4}[/tex]

[tex]\mathbf{c = 6.25}[/tex]

Hence, the possible value of c is 6.25

Read more about mean value theorem at:

https://brainly.com/question/3957181

Answer:

-2.05

Step-by-step explanation:

From the given information,

Let consider [tex]\mu[/tex] to represent the population mean

Therefore,

The null and alternative hypothesis can be stated as :

[tex]H_o :\mu=9[/tex]

[tex]H_1 :\mu<9[/tex]

From the hypothesis , the alternative hypothesis is one tailed (left)

when the level of significance = 0.020, the Z- critical value can be determined from the standard normal distribution table

Hence, the Z-critical value at ∝ = 0.020 is -2.05

Answer:

168 mm²

Step-by-step explanation:

Let A be the area of this shape

the kite is made of two triangles

Let A' and A" be the areas of the triangles

let's calculate A' and A" :

The area of a triangle is the product of the base and the height over 2

Let's calculate A