The water works commission needs to know the mean household usage of water by the residents of a small town in gallons per day. They would like the estimate to have a maximum error of 0.14 gallons. A previous study found that for an average family the standard deviation is 2 gallons and the mean is 16 gallons per day. If they are using a 95% level of confidence, how large of a sample is required to estimate the mean usage of water

Answers

Answer 1

Answer:

A sample of 784 is required to estimate the mean usage of water.

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 Z-table as such z has a p-value 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 standard deviation is 2 gallons

This means that [tex]\sigma = 2[/tex]

They would like the estimate to have a maximum error of 0.14 gallons. How large of a sample is required to estimate the mean usage of water?

This is n for which M = 0.14. So

[tex]M = z\frac{\sigma}{\sqrt{n}}[/tex]

[tex]0.14 = 1.96\frac{2}{\sqrt{n}}[/tex]

[tex]0.14\sqrt{n} = 1.96*2[/tex]

[tex]\sqrt{n} = \frac{1.96*2}{0.14}[/tex]

[tex](\sqrt{n})^2 = (\frac{1.96*2}{0.14})^2[/tex]

[tex]n = 784[/tex]

A sample of 784 is required to estimate the mean usage of water.


Related Questions

Determine whether (a) x = -1 or (b) x = 2 is a solution to this equation

Answers

Answer:

x = 2 is the solution to x + 1.5 = 3.5

Step-by-step explanation:

x + 1.5 = 3.5

   -1.5      -1.5

--------------------

x = 2

find the value and express it in standard form : 5×10^8×2×10^11​

Answers

Answer:

1*10^20

Step-by-step explanation:

5×10^8×2×10^11= 5*2*10^(8+11)= 10*10^19= 10^ (1+19)= 10^20= 1*10^20.

5×10⁸×2×10¹¹5×2×10⁸×10¹¹10×10¹⁹10²⁰100,000,000,000,000,000,0001E20

please mark this answer as brainlist

Make mathematical expressions then, simplify ,50 is divided by 2 times one more than the difference of F and 3.​

Answers

Answer:

F = 27

Step-by-step explanation:

50/2 = (F - 3) + 1

25 = F - 2

F = 27

PLEASE HELP WITH BOTH OF THESE ASAP!

Answers

Answer:

Hello,

Step-by-step explanation:

[tex]\overline{x}=3262\\\sigma=1100\\\\P(x\geq 1000)=P(x\leq 3262+(3262-1000))=P(x\leq 5524)\\\\z=\dfrac{x-\overline{x}}{\sigma} =\dfrac{5524-3262}{1100} =2.05\overline{63}\\\\\\P(z\leq 2.05)=0.9789\\\\P(z\leq 2.06)=0.9803\\\\\\\boxed{0.9789\leq P\leq 0.9803}\\\\\\[/tex]

[tex]P(x\leq 4000)=P(z\leq \dfrac{4000-3262}{1100} )=P(z\leq 0.67\overline{09})\\\\P(z\leq 0.67)=0.7486\\P(z\leq 0.68)=0.7517\\\\0.7486\leq P\leq 0.7517\\[/tex]

6 less than six times a number is 42 what is the number​

Answers

Answer:

x = 8

General Formulas and Concepts:

Pre-Algebra

Equality Properties

Multiplication Property of Equality Division Property of Equality Addition Property of Equality Subtraction Property of Equality

Step-by-step explanation:

Step 1: Define

Identify

6x - 6 = 42

Step 2: Solve for x

[Addition Property of Equality] Add 6 on both sides:                                    6x = 48[Division Property of Equality] Divide 6 on both sides:                                  x = 8

Answer: -6

Step-by-step explanation:

We can create an equation based on the info given.

6-6x=42 Now you solve for x, the unknown number.

-6      -6      Subtract 6 on both sides

-6x=36

/-6   /-6       Divide by -6 on both sides

x=-6

The number is -6.

What steps are included in the construction of a perpendicular line through a point on a line

Answers

Answer:

A perpendicular line from a given point

Place your compass on the given point (point P).

From each arc on the line, draw another arc on the opposite side of the line from the given point (P).

Use your ruler to join the given point (P) to the point where the arcs intersect (Q).

Answer:

get the slope of original line

take the inverse of the slope and multiply by -1 (2/3 becomes - 3/2)

y = -b/a x + b

plug on y & x using the given point

calculate the "B"

go back to the y = -b/ax + calculated "B"

that is your answer

Step-by-step explanation:

yesterday kofi earned 50cedis mowing lawns. today kofi earned 60% of what he earned yesterday mowing lawns.How much did kofi earned mowing lawns today?​

Answers

Answer:

30 cedis

Step-by-step explanation:

todays earning = yesterdays earning * 60/100

50 * 60/100 =30

This answer was confusing for sure

Answers

Answer: lol ez

B.

Step-by-step explanation: XD

Answer:

D

Step-by-step explanation:

The general formula for the sine or cosine function is

y = A*Sin(Bx + C) + D

C = 0 in this case

B = pi / 3

The period is given by the formula

P = 2 * pi / B

P = 2 * pi//pi/3

The 2 pis cancel and you are left with 2*3 = 6

look at the question below in the image

Answers

Answer:

117.8

Step-by-step explanation:

Surface area of a cone = πrl+πr², where r = radius and l = slant height

πrl

= π×3×9.5+π×3²

= 75π/2

= 117.8 (rounded to the nearest tenth)

The table below shows the number of pets kept by the students in a class.
-----------------------------------------------------------
No. of pets | No. of students
-----------------------------------------------------------
0 | 9
1 | k
2 | 2
3 | 1
4 | 2
-----------------------------------------------------------
If the median number of pets is 1, what is the smallest value of k ?

Answers

Answer:

The answer for this question is 5

Determine whether the ordered pair is a solution of the equation. Show your work to receive credit.

9. Is (-1,3) a solution to the equation y = -3x + 10?

10. Is (7,-2) a solution to the equation x – 4y = 15?

Please show work to help me understand.

Answers

Answer:

3=3 + 10

3 = 13(NO)

x-4y=15

7--8=15

15=15(YES)

X
у
Which equation could be used to create the data shown in the
table?
1
5
O y = 5x
4
17
O y = 5x + 1
5
21
O y = 4x + 1
7
29
O y = x + 4
9
37

Answers

Answer:

C

Step-by-step explanation:

The equation that represents the table is y=4x+1

look at the image below

Answers

that's what I got, you can confirm if it's correct or not... I'm not sure

have a nice dayʘ‿ʘ

A garden table and a bench cost $717 combined. The garden table costs $67 more than the bench. What is the cost of the bench?

Answers

Subtract the difference form the total:

717 - 67 = 650

Divide the remaining amount by 2:

650/2 = 375

The bench cost$375

find the LCM of 220,440,660 by common division method​

Answers

Answer: LCM = 1320

Step-by-step explanation:

2 | 220, 440, 660

2 | 110, 220, 330

2 | 55, 110, 165

3 | 55, 55,165

5 | 55, 55 , 55

11 | 11, 11, 11

| 1, 1, 1

= 2 × 2 × 2 × 3 × 5 × 11

= 1320

Therefore the LCM is 1320

Must click thanks and mark brainliest

6 times the sum of 5 and K​

Answers

Answer:

6(5+k)

Step-by-step explanation:

The sum of 5  and k

5+k

6 times the sum

6(5+k)

1. Plot the following points by hand or using an online graphing calculator. What is the function that best fits the points?
(0, 3), (1, 6), (2, 12), (3, 24)

•Linear

•Exponential

•Quadratic

Answers

Exponential. This is an exponential function since it’s being multiplied by a constant rate. That rate is 2. The y axis is constantly being multiplied by 2. 3*2 is 6, 6*2 is 12, 12*2 is 24.

I NEED THE ANSWER SOON PLEASE!!?!?! hopefully someone sees this

Answers

Answer:

1 and 1/25

Step-by-step explanation:

Solve for the value of x

Answers

Answer:

Step-by-step explanation:

This is the Law of Cosines. Use the following formula:

[tex]5.1^2=3.3^2+3.3^2-2(3.3)(3.3)cos(x)[/tex] and simplify to

26.01 = 10.89 + 10.89 - 21.78cos(x) and a bit more to

4.23 = -21.78cos(x) and finally to

-.194214876 = cos(x) and use the 2nd button along with the cos button to find that the missing angle is 101.2 degrees

Cuánto es 324 por 171

Answers

Answer:

la respuesta es 55,404

I hope this helped

by solving a pair of linear equation X + Y is equal to 20 and x-y=10 the value of 'x' and 'y' are​

Answers

Answer:

x=15, y=5

Step-by-step explanation:

x+y=20

x-y=10

Adding both equations;

(x+x) + (y-y) = 20+10

2x = 30

x = 30/2 = 15

Substitute x=15 into x+y=20

y= 20-x = 20-15= 5

If 2/3 of the girls in class have brown eyes and 1/4 of the girls have blue eyes what fraction of the girls in class have neither blue or brown

Answers

1/12, make the denominators the same by making the 12 that makes 8/12 and 3/12 together it’s 11/12 which means 1/12 I not blue or brown

Picking a card and spinning a spinner are independent events.

True
False

Answers

Answer:

True

Step-by-step explanation:

Both happened in different times and are seprate events

Cheyenne's bi-weekly gross pay is $529.81. She sees that $18.54 was deducted for Medicare tax. What percent of Cheyenne's gross pay has been withheld for Medicare tax? Round to the nearest tenth. (2 points)
0.35%
2.2%
3.5%

Answers

18.54/529.81= 0.0349
0.0349*100=3.49%= 3.5%

Answer:

I got 3.5%

Step-by-step explanation:

Hope this helps

2. The cost of 5 pen is Rs 1200, find the cost of 1 pen.​

Answers

Step-by-step explanation:

cost of 5 pen is Rs 1200,

cost of 1 pen is 1200/5 = Rs 240

Answer:

Rs 240

Step-by-step explanation:

1200÷5=240

Canada has a population of 33 million while Russia has 144 million inhabitants. Indonesia population is 50% greater then that of Russia while it is only 72% of the population of the United States. How many million people must be added to the United States so that the population of that country becomes 10 times of Canada?

Answers

Answer: 30 million people must be added.

Step-by-step explanation: 50% of 144 million is 72 million. You add these to find Indonesia’s population. 144 million + 72 million= 216 million. If 216 million is only 72% of the US population, then divide 216 million by 72 to find 1%. 216 million/72=3 million. Multiply this by 100 to find the US population. 3 million times 100= 300 million. Now, multiply Canada’s population by 10. 33 million times 10= 330 million. Finally, subtract 300 million from 330 million to find the amount needed to make the US population 10 times that of Canada’s. 330 million-300 million=30 million. So , you need 30 million people in order to make the US population 10 times that of Canada’s.

In a certain country people own a total of about 352 million fish, cats, and dogs as pets. The number of fish owned is 14 million more than the total number of cats
and dogs owned, and 11 million more cats are owned than dogs. How many of each type of pet do people in this country own?

Answers

Answer:

dogs = 79

dats = 90

fish = 183

Step-by-step explanation:

let the total number of dogs owned be x

no. of cats owned = x+11

no. of fish owned = x+11+x+14= 2x+25

hence,

2x+25+x+11+x=352

4x=316

x=316/4= 79mil

no. of cats owned = 79 + 11 = 90

no. of fish owned = 2(79)+25=183

The polynomial p(x) = x3 – 7x - 6 has a known factor of (x + 1).
Rewrite p(x) as a product of linear factors.
p(x)

Answers

Hi there!

[tex]\large\boxed{(x -3)(x + 2)(x + 1)}[/tex]

We can use long division to find the other roots of p(x).

We know that x + 1 is a factor, so:

Set up:

Find how many times that the first term in the divisor goes into the first of the dividend. Subtract from like terms.

         x² - x - 6

x + 1 | x³ + 0x² - 7x - 6

         x³ + x²

         0 - x²     - 7x

            - x²      - x

             0        - 6x - 6

                        -6x - 6

                          0     0

Therefore, x² - x - 6 is another factor. We can factor this further:

Find two numbers that add up to -1 and multiply into -6. We get:

-3, 2

(x - 3)(x + 2)

The entire polynomial factored is:

(x -3)(x + 2)(x + 1)

Select the correct answer.
As part of a class project, a university student surveyed the students in the cafeteria lunch line to look for a relationship between eye color and hair color among students. The table below contains the results of the survey.

Answers

Answer: Choice B)  0.27

=========================================================

Explanation:

There are a lot of data values here, and it's possible to easily get lost in them. However, we're asked only about students with blond hair. So we only focus on the first row. Ignore everything else.

We see that there are 78 of these students total. Of this total, 21 have green eyes.

Therefore, the relative frequency of blonds with green eyes is 21/78 = 0.2692 which rounds to 0.27; so that's why the answer is choice B.

Chen rode his skateboard 3/3/4 miles in 34 of an hour.

What was his average speed in miles per hour?

_[blank]_ miles per hour

Answers

Answer:

5 miles per hour

Step-by-step explanation:

3¾ ÷ ¾ =

15/4 ÷ ¾ =

15/4 x 4/3 =

15/3 = 5

Other Questions
Ajax, Inc., issued callable bonds with a par value of $1,000,000 that require the payment of a call premium of $10,000. The bonds have a carrying value of $990,000. We call these bonds prior to maturity on September 30. Required:Write down journal entry. a call centre aims to deal with calls in less than 5 minutescalls come in randomly A municipality is issuing 40,000 bonds at a public offering price of $1,000. The manager of the underwriting syndicate receives $1.50 per bond. The total takedown is $6.50 per bond and the selling concession is $4.00 per bond. Assume the entire issue is sold with the selling group distributing 20,000 of the bonds sold. Calculate the amount of compensation the syndicate will receive for its risk on selling group sales Pls help Which of the following exponential equations is equivalent to the logarithmic equation below ? In x = 7 IM GIVING BRAINLESIT AND ANYTHING UNDER 20$ ON ANY APPROPIATE CURRENCY IF YOU ANSWER ALL OF THIS (PLEASE LABEL WHAT YOUR ANSWERING) For the equation, determine whether the equation is true for all, some, or no values of x.Explain how you know.3x=x3 what does porous mean SOVE, REDUCE TO LOWEST TEERMS SIMPLIFY IMPROPER FRACTIONSAS MIXED FRACTIONS what is the answer to x if 2x = 7 Translate the following paragraph into Spanish. Hello. My name is Francisco Lara. I live in Magic Ranch. I am a new student at the school. I am from New York. I am in the 11th grade. I want to play on the school football team. I like to play sports and also watch movies. I do not like the heat inArizona. I have two older sisters. They are in the 12th grade. They like to study and get good grades. I am not as intelligent as they are but I always get good grades. Qu pasa si repruebo una materia en el ltimo ao de secundaria? Y que puedo hacer para aprobarla? Find the greatest number of students to whom 45 soccer balls and 60 tennis balls can be equally divided. The purpose of an analysis of an account is to illustrate - in the account for the period under audit x and y are integers and 0 < x < y.Write down two sets of values for x and y such that 6 = /3x+2y. Going outside the home alone, being in a crowd, standing in line, or riding in a car can be impossible for people with which disorder who fear that something extremely embarrassing will happen if they leave home or enter an unfamiliar situation 4) Programming a) WAp to find the greatest number among any three numbers. Which of the following is an example of combustion?O A. potassium chlorate -> potassium chloride + oxygenB. aluminum + cobalt chloride -> aluminum chloride + cobaltO c. hexane + oxygen carbon dioxide + waterOD. sodium cyanide + hydrochloric acid -> sodium sulfate + hydrogen cyanide Case law comes from court rulings.True or false 12 workers take 4 hours to complete a job. How long would it take 15 workers to complete the job? If the price of a haircut is $15, the number of haircuts provided is 100. If the price rises to $30 per haircut, barbers will work much longer hours, and the supply of haircuts will increase to 300.Instructions: Round your answers to two decimal places.The price elasticity of supply for haircuts between $15 and $30 using the mid-point method is:________.