An article in the November 1983 Consumer Reports compared various types of batteries. The average lifetimes of Duracell Alkaline AA batteries and Eveready Energizer Alkaline AA batteries were given as 4.1 hours and 4.5 hours, respectively. Suppose these are the population average lifetimes.

Required:
Let x̄ be the sample average lifetime of 64 Duracell and ȳ be the sample average lifetime of 64 Eveready Energizer batteries. What is the mean value of x̄- ȳ(i.e., where is the distribution of -centered)?

Answers

Answer 1

Answer:

The mean is of -0.4 hours.

Step-by-step explanation:

To solve this question, 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.

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.

Mean of the sample of 64 Duracell:

By the Central Limit Theorem, 4.1 hours.

Mean of the sample of 64 Eveready:

By the Central Limit Theorem, 4.5 hours.

Mean of the difference?

Subtraction of normal variables, so we subtract the means.

4.1 - 4.5 = -0.4

The mean is of -0.4 hours.


Related Questions

Write the equation of a line in slope intercept form that passes through the two points. (-1,3) and (2,9)

Answers

Answer:

[tex]y = 2x +5[/tex]

Step-by-step explanation:

Finding the Slope:

m = rise/run

[tex]m=\frac{9-3}{2-(-1)}=\frac{6}{3}=\boxed{2}[/tex]

The slope is 2.

Finding the y-intercept:

[tex]y = 2x + b\\\\9 = 2(2) + b\\\\9 = 4 + b\\\\9 - 4 = 4 - 4 + b\\\\\boxed{ 5 = b}[/tex]

The y-intercept is (0,5).

The equation should be: [tex]y = 2x +5[/tex].

Hope this helps.

Answer:

y = 2x+5

Step-by-step explanation:

To find the equation in slope intercept form, we first have to find the slope of the two points.

The formula for finding the slope is:

[tex]\frac{y2-y1}{x2-x1}[/tex]

We are given the points:

(-1, 3) and (2, 9)

x1, y1 and x2, y2.

[tex]\frac{9-3}{2-(-1)}[/tex]

[tex]\frac{6}{3}[/tex] or 2 (the slope).

The slope intercept form is written as:

y= mx + b

y=2x+b

To find b, we can plug in either of the points given. Personally, I like to work with positive numbers. I'll be using the point (2, 9), however, either point will get you to the same answer.

y=2x+b

9=2(2)+b

9=4+b

Now subtract 4 from both sides.

5=b

Which then leaves us with the equation:

y = 2x+5

Graph 5 and it’s opposite on the number line

Answers

Answer:

See pic below.

Step-by-step explanation:

The opposite of 5 is -5.

HELP PLEASE! INEEED HELPPP RIGHT NOW The graph of y=x−2−−−−√ is is transformed to become y=x+3−−−−√−2. Which of the following statements best describes the effect this transformation has on the graph of y=x−−√?

Answers

Answer:

I think it's D but I don't know how to do this, but I ask my Friend and he gave me this graph I hope it helps.

Option (C) the graph is translated 5 units left and 2 units down is the correct answer.

What is graph of a function?

A graph can be defined as a pictorial representation or a diagram that represents data or values in an organized manner. The graph of a function f is the set of all points in the plane of the form (x, f(x)).

For the given situation,

The function is [tex]y=\sqrt{x-2}[/tex]

This function is transformed to become the function as [tex]y=\sqrt{x+3}-2[/tex]

Now compare this transformation with the function [tex]y=\sqrt{x}[/tex].

These functions are plotted in the graph below.

On comparing this transformation,

The graph is translated 5 units left and 2 units down.

Hence we can conclude that option (C) the graph is translated 5 units left and 2 units down is the correct answer.

Learn more about graph of a function here

https://brainly.com/question/2275360

#SPJ2

If an 8" X 8" square cake serves 8 people, how many 24" X 24" square cakes are needed for a
wedding attended by 144 people?

Answers

Answer:

2 24" X 24" square cakes are needed.

Step-by-step explanation:

This question is solved by proportions.

Area of a square:

The area of a square of side l is given by:

[tex]A = l^2[/tex]

8" X 8" square cake serves 8 people

Thus:

[tex]A = 8*8 = 64[/tex]

Area of 64 serves 8 people, so for 1 people, an area of 64/8 = 8 is needed.

144 people

The total area needed is:

[tex]A = 144*8 = 1152[/tex]

How many 24" X 24" square cakes?

24*24 = 576

1 cake - 576

x cakes - 1152

Applying cross multiplication:

1152/576 = 2

2 24" X 24" square cakes are needed.

g U is the set of in the United States. A is the set of in the United States that have the in their name. B is the set of in the United States that have the in their name. Describe the set in words. Choose the correct answer below. A. is the set of in the United States that have the . B. is the set of in the United States that have the . C. is the set of in the United States that have the . D. is the set of in the United States that have the .

Answers

Question isn't well formatted   picture if actual question is attached below :

Answer:

A' set of colleges in the United States which Don not have the word community in their name.

Step-by-step explanation:

If a universal set U is defined as :

U =set of colleges in the United States.

A = the set of colleges in the United States that have the word community in their name.

B is the set of colleges in the United States that have the name of an entertainer in their name.

The set A' is called the A complement. The complement of a particular refers to elements in the universal set which are not in A ;

A' = 1 - A'

Therefore, A' set of colleges in the United States which Don not have the word community in their name.

Volunteering: The General Social Survey asked 1309 people whether they performed any volunteer work during the past year. A total of 518 people said they did. Part: 0 / 30 of 3 Parts Complete Part 1 of 3 (a) Find a point estimate for the population proportion of people who performed volunteer work in the past year. Round the answer to at least three decimal places. The point estimate for the proportion of people who performed volunteer work in the past year is .

Answers

Answer:

The point estimate for the population proportion of people who performed volunteer work in the past year is 0.396.

Step-by-step explanation:

Point estimate of a proportion:

Proportion is the number of desired outcomes divided by the number of total outcomes.

518 out of 1309 people performed volunteer work:

This means that:

[tex]p = \frac{518}{1309} = 0.396[/tex]

The point estimate for the population proportion of people who performed volunteer work in the past year is 0.396.

What is the range & domain of the set
R: {(-6, 14), (10,19), (4, -9), (3, 2), (6, -13)}

Answers

Answer:

Domain { -6,3,4,6,10}

The range is the output values, listed from smallest to largest with no repeats

Range { -13,-9,2,14,19}

Step-by-step explanation:

The domain is the input values, listed from smallest to largest with no repeats

Domain { -6,3,4,6,10}

The range is the output values, listed from smallest to largest with no repeats

Range { -13,-9,2,14,19}

Answer:

Range: 14, 19, -9, 2, -13

Domain: -6, 10, 4, 3, 6

Step-by-step explanation:

I don't know but this is it I think .

The price of the cinemas meal deal has increased from £7.25 to £9.28.
What is the percentage change in price?

Answers

ejheheksjshdhdhgdgege is a irtel of the main thing is mute the main 22sec and jen best friends movie is mute the main thing for kids are vaccine safe to make a diy boat 6main thing for kids are vaccine the main thing for kids are vaccine safe 6to make a diy boat main 6thing for kids are vaccine safe 66G PHONE is a diy plane to the 7main thing for kids are vaccine

Answer:

8.28% increase i believe

Step-by-step explanation:

formula: final amount - initial ÷ initial amount.

9.28-7.25= 2.03. now divide by the initial amount. 2.03÷7.25=8.28.

so, an 8.28% increase to the price

help i’ll give brainliest

Answers

-4

explination: the x-intercept is where the line touches the X line kn the graph, the line intercepts at -4

Answer:

(0,-4)

Step-by-step explanation:

The plot for x intercept is at -4,0 and the y intercept is at 0,5

type it in as (0,-4), some require the (#,#) format

If y varies directly as x, and x = 4 when y = 20, find y when x = 18.

Answers

Step-by-step explanation:

y=Kx

20=4k

k=5

when x=18

y=18 x 5

y=90

here's a graph of a linear function write the equation that describes the function express it in slope-intercept form

Answers

Answer:

y = 3/4 x - 3

Step-by-step explanation:

the slope of a line is the factor of x in the equation and is expressed as ratio of y/x : defining how many units y changes, when x changes a certain number of units.

in our graph here we can see that when increasing x from e.g. 0 to 4 (the x-axis intercept point, a change of +4), y changes from -3 to 0 (a change of +3).

so, the slope and factor of x is y/x = 3/4

and for x=0 we get y=-3 as y-axis intercept point.

so, the line equation is

y = 3/4 x - 3

190 of 7
6 7 8 9 10
-3
4
5
6
The slope of the line shown in the graph is
and the intercept of the line is

Answers

Answer:slope 2/3

Y-int 6

Step-by-step explanation:

which shape is both a parallelogoram and a rhombus

Answers

Answer:

A square can be defined as a rhombus which is also a rectangle and a parellelogram with four congruent sides and four right angles

I hope this helps

Một công ty sản xuất một thùng hình trụ tròn không có nắp và có thể tích 8x ft Chi phí sản xuất đáy là 2 USD / ft ?, chi phí sản xuất mặt bên là 4,8 USD / ft . Hỏi chi phí tối ưu nhất để sản xuất cái thằng này là bao nhiêu USD ?,

Answers

Answer:

nsjdjdnajakla ,bxn. dnsksksvhdjeke dkekdkbdjdls d

(b) In a company, out of 20 candidates 14 men and 6 women apply for two vacancies. What is the probability that (1) both men are selected ? (ii) both women are selected ? (iii) one man and one woman are selected ?​

Answers

i hope my answer helps you and you will give me the best answer

Let f(x, y) = 2xy − 3xy + y + 1. Find the derivative of f with respect to y.

Answers

Answer:

2x-3x+1

Step-by-step explanation:

f'(x,y)=2x-3x+1

Mrs Lee had $7500 in her bank account. The bank paid 4% interest at the
end of each year. How much did she have in the bank at the end of 1 year?

Answers

Answer:

$7800

Step-by-step explanation:

1. Principal x interest x rate

So: $7500 + 4% (0.04) x 1 year = $300

2. Interest + Principal

So: $7500 + $300

Mrs Lee had $7800 in the bank.

A manufacturing process produces bags of cookies. The distribution of content weights of these bags is Normal with mean 15.0 oz and standard deviation 1.0 oz. We will randomly select n bags of cookies and weigh the contents of each bag selected. How many bags should be selected so that the standard deviation of the sample mean is 0.1 ounces?

a. 8 bags
b. 10 bags
c. 64 bags
d. 100 bags

Answers

Answer:

100 bags

Step-by-step explanation:

S.E = σ/ √n

0.1 = 1 / √n

Square both sides

0.1² = 1² / n

0.01 = 1 / n

0.01n = 1

n = 1 / 0.01

n = 100

how do you change 79/8 to a decimal

Answers

Explanation: Divide it


Answer: 79/8=9.875

Answer:

Divide 79 by 8

Step-by-step explanation:

79/8

= 9.875

what is the square root of 24

Answers

Answer:

the square root of 24 is 4.89897948557

Answer:

4.89

Step-by-step explanation:

2root 6........***

I need help with just 1 and 2

Answers

1. I think in Brooklyn, Manhattan, and the other different cities in New Jersey, the rents are overpriced.

2. Some factors are if it looks nice, there are no bugs or rodents, and if it's not a rip off.

**I can't answer the second part bcuz i don't see the tables.  

Question 8
A student earned 30 out of 35 points on a
the total points did the student earn? Round it off to the nearest precent

Answers

The percent is 85.71% so the rounded answer would be be 86%
To do this put into the calculator 30 divided by 35, which will get you about 0.8571 and for percentage you multiply it by hundred so that will get you about 85.71% and then round it to the nearest percentage, and since 7 is greater then 5 you would round up so your rounded percentage would be 86%

a store sells pencils pens and markers that sells two times as many markers as pencils and three times as many pens as pencils is the store sells a total of 1950 pencils and pens and markers in a week how many of each were sold​

Answers

Answer:

Pencils = 325 ; Pens = 975 ; Markers = 650

Step-by-step explanation:

Let :

Number of Pencils = x

Number of pens = y

Number of markers = z

2 times as many markers as pencils

z = 2x

3 times as many pens as pencils

y = 3x

x + y + z = 1950

Write z and y in terms of x in the equation :

x + 3x + 2x = 1950

6x = 1950

Divide both sides by 6

6x / 6 = 1950 / 6

x = 325

Number of pencils = 325

Pens = 3 * 325 = 975

Markers = 2 * 325 = 650

Pencils = 325 ; Pens = 975 ; Markers = 650

What is the Square root of 30 ,12,36

Answers

Answer:

the square root of:

30: 5.477225575

12: 3.464101615

36: 6 <-- explanation of square root: any number that when multiplied by itself equals your wanted number (in this case 36) will be the square root of your wanted number.

1 Construct the following triangles. You will need a ruler and a protractor.
a) Triangle ABC, where AB = 5 cm,

Answers

Answer:

abcdefghijklmnopqrstuvwxy and z

Step-by-step explanation:

caron makes $6 every 30 minutes. using the double number line diagram below, how much money would she make if she worked 80 minutes at the same rate?

Answers

Answer:

$16

Step-by-step explanation:

Both lines start at 0 and at 30 mins it is $6. It displays a ratio so that means every 10 mins they earn $2

The graph below represents which of the following functions?

Answers

Answer:

hiuu ui9i io9

Step-by-step explanation:

iu9uj k

Solve 9(7x-2) = 5 (10x - 1)​

Answers

Answer:

[tex]9(7x - 2) = 5(10x - 1) \\ \\ 63x - 18 = 50x - 5 \\ \\ 63x - 50x = - 5 + 18 \\ \\ 13x = - 5 + 18 \\ \\ 13x = 13 \\ \\ x = \frac{13}{13} \\ \\ x = 1[/tex]

Answer:

[tex]9(7x - 2) = 5(10x - 1) \\ 9 \times 7x - 9 \times 2 = 5 \times 10x - 5 \\ 63x - 18 = 50x - 5 \\ 63x - 50x = - 5 + 18 \\ 13x = 13 \\ x = 1 \\ thank \: you[/tex]

There is a language with 12 distinct letters. How many words that are less than four letters long can possibly be formed? (Assume any combination of letters is valid and letters can be repeated). Can you help me out with this one?

Answers

Answer:

1884

Step-by-step explanation:

1)If you hear the condition "less than four letters" it means that each word can consist of 3,2 or 1 letter. Firstly, consider the easiest situation with the word from one letter. There are 12 letters, so there are 12 words from one letter.

Then the words from two letters. The first letter of such a word can be chosen in 12 means(because 12 letters are available), then the second letter can be chosen in 12 means too. 12*12=144 words with 2 letters. (Multiplying, not adding, because each two words form one combination).

Then for the words from three letters, use the same rule, 12 means for the first letter, 12 means for the second letter, 12 means for the third letter. 12*12*12=1728 words.

Having particular words from 1,2,3 letters add them to get total quantity of words: 12+144+1728=1884words,that is the answer.

NO LINKS OR ANSWERING QUESTIONS YOU DON'T KNOW. Find each measurement. Round your answers to the nearest tenth. Part 2dd​

Answers

Answer:

see explanation

Step-by-step explanation:

Using the Sine rule in all 3 questions

[tex]\frac{a}{sinA}[/tex] = [tex]\frac{b}{sinB}[/tex] = [tex]\frac{c}{sinC}[/tex]

(2)

[tex]\frac{b}{sinB}[/tex] = [tex]\frac{c}{sinC}[/tex] , substitute values

[tex]\frac{45}{sin133}[/tex] = [tex]\frac{c}{sin26}[/tex] ( cross- multiply )

c × sin133°  = 45 × sin26° ( divide both sides by sin133° )

c = [tex]\frac{45sin26}{sin133}[/tex] ≈ 27.0 ( to the nearest tenth )

(4)

[tex]\frac{b}{sinB}[/tex] = [tex]\frac{c}{sinC}[/tex] , substitute values

[tex]\frac{19}{sinB}[/tex] = [tex]\frac{30}{sin97}[/tex] ( cross- multiply )

30 sinB = 19 sin97° ( divide both sides by 30 )

sinB = [tex]\frac{19sin97}{30}[/tex] , then

∠ B = [tex]sin^{-1}[/tex] ( [tex]\frac{19sin37}{30}[/tex] ) ≈ 38.9° ( to the nearest tenth )

(6)

[tex]\frac{b}{sinB}[/tex] = [tex]\frac{c}{sinC}[/tex], substitute values

[tex]\frac{18}{sin102}[/tex] = [tex]\frac{xAB}{sin45}[/tex] ( cross- multiply )

AB sin102° = 18 sin45° ( divide both sides by sin102° )

AB = [tex]\frac{18sin45}{sin102}[/tex] ≈ 13.0 ( to the nearest tenth )

Other Questions
Read this short story, and write the correct imperfect forms of the verbs in parentheses in the space provided below. Be sure to number your answers.Un Da en la Escuela(1)___Ser)___ lunes. A Paco no le (2)___(gustar)___ los lunes porque (3)___(tener)___ que ir a la clase de ingls. El amigo de Paco se (4)___(llamar)___ Pepe. Paco y Pepe siempre (5)___(Ir)___ juntos a la clase de ingls. El maestro de la clase de ingls se llamaba Seor Alcachofa. El Seor Alcachofa era muy exigente. El problema era que Paco no (6)___(haber)___ hecho su tarea. Mientras Paco (7)___(pensar)___ en una excusa, su amigo Pepe le dijo "Puedes copiar mi tarea." Paco lo (8)___(considerar)___ mientras (9)___(esperar)___ que empezara la clase. Entonces, Paco pens en las palabras de su padre: "Honra y dinero se ganan despacio y se pierden ligero." Paco decidi ser honesto y dijo sinceramente al Seor Alcachofa que no hizo su tarea. Despus de hacerlo, Paco se sinti mejor. Paco (10)___(saber)___ que haba hecho lo justo.Can you just make the numbered words in imperfect form? Which equation relates the population (P) in millions to the time that has passed (T) if the growth rate is 4% per year and the startingpopulation is 10 million people?(1) P = 10(0.96)^T(2) P = 10(1.04)^T(3) P = 10 + 10(0.04)^T(4) P = 10(1.4)^T Can you guys help me please ? Date:04/09 Pages35 5) How does a common religion help the growth of nationality? A juice machine is set to dispense 16 ounces of juice. The amount of juicedispensed is normally distributed, with a mean of 16.15 ounces and astandard deviation of 0.25 ounces. In which range will the amount of juicedispensed be found 68% of the time? Un cuerpo es saltado desde cierta altura , llegando al piso luego de 7 s. Determine de altura se le solt . (g=10m/segundo al cuadrado ) which expression is equivalent to c^2 - 4 / c + 3 / Victor had dozen boxes, with n number of water bottles in each box. After removing dozen bottles, there were 84 bottles. Find the number of bottles in each box. As you prepare to organize an academic paper, what's the first thing you should do?A. Type up your detailed notes on your research.B. Write a formal outline using full sentencesC. Double-check the requirements of the assignment.D. Put all your ideas in order from most to least important in two or more complete sentences, describe how to graph the following equation. in your description, include the slope and both the x- and y-intercepts of the line. y=2 e) Three friends were each given 25% of pie. What fraction of the pie was given altogether? HELP ME PLSSSSS I NEED HELP PLS PLS PLS ITS PYTHAGOREAN THEOREM 4.Read the sentence and answer the question.My mother and father practice the viola with the Cleveland Orchestra on Saturday and I stay home to practice the violin.Which correctly shows where a comma is needed in the sentence?A. My mother, and father practice the viola with the Cleveland Orchestra on Saturday and I stay home to practice the violin.B. My mother and father practice the viola with the Cleveland Orchestra on Saturday, and I stay home to practice the violin.C. My mother and father practice the viola with the Cleveland Orchestra on Saturday and I stay home, to practice the violin.D. My mother and father practice the viola, with the Cleveland Orchestra on Saturday and I stay home to practice the violin. Which of the following have a total of 8 possible outcomes? Check all that apply. Select the correct answer from each drop-down menu. The asymptote of the function f(x) = 3x + 1 2 is ____ Its y-intercept is ____ Describe the role chemical signals play a role in both the nervous system and the endocrine system Question 8 of 10If f(x) = 4x2 and g(x) = x+1, find (fg)(x).A. 4X2 + 1B. 4x2 + 4x2C. 4(x+1)D. 4x(x)SURVIT Which of the following examples best represents the use of an interval scale? measuring the number of cookie boxes sold by scouts on the west coast of a town versus those sold on the east coast of the town naming the different car brands seen in a school's parking lot assessing students' ratings of their professors' performance on a five-point scale ranging from poor to excellent ranking the participants of a race based on their performance 21 is 35% of what number (shown work) evaluate the expression. check all possible sets that the solution may belong in. 40-5^2