A fitness center is interested in finding a 90% confidence interval for the mean number of days per week that Americans who are members of a fitness club go to their fitness center. Records of 219 members were looked at and their mean number of visits per week was 2.4 and the standard deviation was 2.9. Round answers to 3 decimal places where possible.
A. The sampling distribution follows a _______ distribution.
B. With 90% confidence the population mean number of visits per week is between _____ and ______ visits.
C. If many groups of 220 randomly selected members are studied, then a different confidence interval would be produced from each group. About ________ percent of these confidence intervals will contain the true population mean number of visits per week and about__________ percent will not contain the true population mean number of visits per week.

Answers

Answer 1

Answer:

A. Normal

B. Between 2.078 and 2.722 visits.

C. About 90 percent of these confidence intervals will contain the true population mean number of visits per week and about 10 percent will not contain the true population mean number of visits per week.

Step-by-step explanation:

Central Limit Theorem

The Central Limit Theorem estabilishes 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.

For a proportion p in a sample of size n, the sampling distribution of the sample proportion will be approximately normal with mean [tex]\mu = p[/tex] and standard deviation [tex]s = \sqrt{\frac{p(1-p)}{n}}[/tex]

x% confidence interval:

A confidence interval is built from a sample, has bounds a and b, and has a confidence level of x%. It means that we are x% confident that the population mean is between a and b.

Question A:

By the Central Limit Theorem, normal.

Question B:

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 - 0.9}{2} = 0.05[/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 - 0.05 = 0.95[/tex], so Z = 1.645.

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.

[tex]M = 1.645\frac{2.9}{\sqrt{219}} = 0.322[/tex]

The lower end of the interval is the sample mean subtracted by M. So it is 2.4 - 0.322 = 2.078 visits

The upper end of the interval is the sample mean added to M. So it is 2.4 + 0.322 = 2.722 visits.

Between 2.078 and 2.722 visits.

Question c:

90% confidence level, so 90% will contain the true population mean, 100 - 90 = 10% wont.

About 90 percent of these confidence intervals will contain the true population mean number of visits per week and about 10 percent will not contain the true population mean number of visits per week.


Related Questions

number of bacteria in a certain population Increases according to a continuous exponential growth model with How many hours does it take the size of the sample to double ? growth rato parameter of 48% per hour

Answers

Answer:

It takes 1.77 hours for the population to double.

Step-by-step explanation:

Equation for population growth:

The equation for population growth, after t hours, with a growth rate parameter of r, as a decimal, is given by:

[tex]P(t) = P(0)(1+r)^t[/tex]

Growth rato parameter of 48% per hour

This means that [tex]r = 0.48[/tex]. So

[tex]P(t) = P(0)(1+r)^t[/tex]

[tex]P(t) = P(0)(1+0.48)^t[/tex]

[tex]P(t) = P(0)(1.48)^t[/tex]

How many hours does it take the size of the sample to double?

This is t for which P(t) = 2P(0). So

[tex]P(t) = P(0)(1.48)^t[/tex]

[tex]2P(0) = P(0)(1.48)^t[/tex]

[tex](1.48)^t = 2[/tex]

[tex]\log{(1.48)^t} = \log{2}[/tex]

[tex]t\log{1.48} = \log{2}[/tex]

[tex]t = \frac{\log{2}}{\log{1.48}}[/tex]

[tex]t = 1.77[/tex]

It takes 1.77 hours for the population to double.

please help im stuck on this question​

Answers

Answer:

(12,0)

Step-by-step explanation:

slope m=

[tex]\frac{54-36}{27-22} =\frac{18}{5}[/tex]

[tex]y-36=\frac{18}{5}(x-22)\\\\5y-180=18x-396\\\\y=\frac{18x}{5} -\frac{46}{5}[/tex]

[tex]0=\frac{10}{5}x-\frac{46}{5}\\\\x=\frac{216}{18} =12[/tex]

hope it helps...

have a great day

Find the circumference of the circle and round to the nearest tenth

Answers

Answer:

circumference of circle = 2×pi×r

circumference of circle = 2×3.14×12.7

circumference of circle = 79.756 in

20POINTS! Determine if two triangles are congruent. If they are, state which theorem you can use to prove congruency. EXPLAIN WHY OR ELSE I WILL REPORT.

Answers

Answer:

both each side of each triangle is equal

use alphabets to mark each edge of the triangles and prove congruency

NEED ANSWER ASAP WILL GIVE BRAINLIEST FOR CORRECT ANSWER

Answers

Answer:

Slope

Step-by-step explanation:

Hope it helps you in your learning process

A quadrilateral is inscribed in a circle. Find the measure of each missing angle as labeled below. explain answer please

Answers

9514 1404 393

Answer:

C = 95°D = 72°F = 108°

Step-by-step explanation:

Opposite angles of an inscribed quadrilateral are supplementary. Inscribed angles are half the measure of the arc they subtend. (The latter statement can be used to prove the former one.)

Using these relations, we have ...

  C = 180° -E = 180° -85° = 95°

  D = 144°/2 = 72°

  F = 180° -D = 180° -72° = 108°

Does anyone know what the answer please?

Answers

Answer:

[tex]\angle 1 \cong \angle 7[/tex]

Step-by-step explanation:

We proceed to present which angles corresponds with [tex]\angle 7[/tex], accompained with reason based on Theorems used in Euclidean Geometry. Two angles are correspondent if and only if are in the same side of the secant line, one of them is internal and the other one is external.

Hence, we conclude that [tex]\angle 1 \cong \angle 7[/tex].

Devon, Tony, and Nate were playing a board game. Devon wins when the spinner lands on green. Nate wins when the spinner lands on blue. Tony wins when the spinners lands on red. Which spinner should be used to make the game fair?

Answers

Answer:

c

Step-by-step explanation:

Weisen Sie bei folgenden Rechnungsbeträgen die Mehrwertsteuer aus!

a) 124,30 € b) 69,30 c) 12,50 €

Answers

Answer:

hj0

Step-by-step explanation:

Hi0 c cbdjdnsnsns d s

what is the meaning of kiss

Answers

Answer:

wrong subject but, kiss means i guess to lock lips in a passionate way or in a greeting way. In some countries kissing someone on the cheek or past the cheek is a sign of a greeting i believe.

In short kissing means a way to show compassion or love.

Find each measurement indicated. Round your answers to the nearest tenth.

Answers

Answer:

52.08°

Step-by-step explanation:

Law of sine: [tex]\frac{93}{25}[/tex]=[tex]\frac{x}{14}[/tex]

93*14=25x

1302=25x

52.08=x

A coat cost $37.88 at Walmart. The sales tax is 5.5%. What is the total amount of the coat including the sales tax?​

Answers

$39.96 should be ur answer

There are 10 red apples and 12 green apples in a basket. If Vinta randomly selects 3 apples from
the basket, what is the probability they will all be green apples?

Answers

Answer: 1/7

Step-by-step explanation: 12/22 • 11/21 • 10/20

The probability they will all be green apples is 0.142 if there are 10 red apples and 12 green apples in a basket.

What is probability?

It is defined as the ratio of the number of favourable outcomes to the total number of outcomes, in other words, the probability is the number that shows the happening of the event.

As we know,

A permutation is the number of different ways a set can be organized; order matters in permutations, but not in combinations.

It is given that:

There are 10 red apples and 12 green apples in a basket. If Vinta randomly selects 3 apples from the basket.

Total outcomes = number of ways of selecting fruits in the basket

Total fruits = 10 + 12 = 22

Total number of outcomes = C(22, 3) = 1540

Total number of favourable outcomes = C(12, 3) = 220

Probability = 220/1540

Probability = 0.142

Thus, the probability they will all be green apples is 0.142 if there are 10 red apples and 12 green apples in a basket.

Learn more about the probability here:

brainly.com/question/11234923

#SPJ2

Jennifer made a baby blanket that is 2 feet by 3 feet. She has a queen size blanket that is 6 feet by 9 feet. How does the area of the baby's blank t compare to the size of the queen sized blanket?

Answers

The area of the baby blanket is 6 feet. The area of the queen size is 54 feet.
The area of the baby blanket is 9x smaller.

The area of the queen sized blanket is 9 times bigger than the area baby blanket.

What is the area of a rectangle?

The area of a rectangle is the multiplication of it's length and breadth.

Here, the area of the baby blanket = 2 × 3 square feet = 6 square feet.

The area of the queen sized blanket = 6 × 9 square feet = 54 square feet.

Therefore, the ratio of the baby blanket : queen sized blanket

= 6 : 54

= 1 : 9

Hence, area of the queen sized blanket is 9 times bigger than the area baby blanket.

Lear more about the area of the rectangle here: https://brainly.com/question/24408520

#Tag #SPJ2

C = 172.7 cm
Use the formula, c = ad, and x = 3.14, to find the diameter of this circle whose circumference equals 172.7 cm.
A. 55 cm
B. 27.5 cm
O c. 542.278 cm
D. 5.5 cm
O E. 86.35 cm

Answers

Answer:

B

Step-by-step explanation:

In this diagram use pythagoras theorem to calculate the length of the marked side

Answers

Answer:

[tex] 5\sqrt{7} [/tex]

Step-by-step explanation:

using Pythagoras theorem

[tex]d = \sqrt{ {20}^{2} - {(15)}^{2} } \\ [/tex]

[tex]d = 5 \sqrt{7} [/tex]

Step-by-step explanation:

Hyponues²= Base²+Height ²

20cm²=Base²+15cm²

400cm-225cm=H²

175=H²

5√7 Answer

I need to find the area!
Plz help me find the answer!

Answers

ANSWER:

680 sq units

MARK ME BRAINLIEST PLEASE

Please help, find the value of y

Answers

Answer

Step-by-step explanation:

chord makes  or arc make 120° at the center.

sum of other two angles of triangle=180-120=60

because they are equal.

so each angle=60/2=30°

tangent line makes angle 90° with radius .

so 30+y=90

y=90-30=60°

y=-2
4x-3y=18
solve for x and y

Answers

No need to solve for y. The value of y is given. See it?

To find x, plug the given value of y into

4x - 3y = 18.

4x - 3(-2) = 18

4x + 6 = 18

4x = 18 - 6

4x = 12

x = 12/4

x = 3

Answer: y = -2 and x = 3.

Understand?

Answer:

X=3 y=-2

Step-by-step explanation:

4x-3y=18

4x-3(-2)=18

4x+6=18

4×=18-6

4x=12

divide both sides by 4

X=3

A cone has a radius of 7 m and a height of 18 m . What is the approximate volume of the cone to the nearest tenth? Use 3.14 for pie

Answers

The answer is 923.2 because I found the circumference of the circle which was 153.86 and since it is the volume of the cone you would use the formula V=1\3BH. Using that formula you would do: 1/3*153.86(18) and that would get you 923.16 and since it looks like the answer wants you to round, you would get 923.2. Hope that helps!

Between which values does 111 lie?
A. 7 and 8
B. 8 and 9
C. 9 and 10
D. 10 and 11
E .11 and 12

Answers

Answer: D: 10 and 11

Step-by-step explanation:

The Sq Rt of 111 is 10.5356537529 which falls between 10 and 11

Answer:

D: 10 and 11

Step-by-step explanation:

10.5356537529 10^11

and in standard notation:

105,356,537,529

Find the value of x in the isosceles triangle below then find the measure of the base angle.
x = __°
Measure of 1 base angle = __°

Answers

Answer: [tex]x=13[/tex], one base angle measures [tex]74^{\circ}[/tex]

Step-by-step explanation:

The base angles of an isosceles triangle are congruent, so:

5x + 9 = 8x - 30 [congruent angles have equal measure]9 = 3x - 30 [subtract 5x from both sides]39 = 3x [add 30 to both sides]x = 13 [divide both sides by 3]

Hence, the measure of one base angle is [tex]5(13)+9=\boxed{74^{\circ}}[/tex]

What is the area of a square that has 2/4 units on each side

Answers

Answer:

1/4 of 0.25

Step-by-step explanation:

2/4 x 2/4 = 1/4

T or F: If you consume more calories, you must decrease your physical activity to have energy
balance.
(not math but for pe)

Answers

Answer:

F

Step-by-step explanation:

When your losing weight after consuming more calories, you need to increase physical activity to increase the number of calories your body uses for energy.

T because if you consume more calories you will need to descrease ur physical activity

Find the area of the figure. Round to the nearest tenth.
6.5
3
O 14.6 units2
O 22.4 units2
15.0 units2
O 18.2 units2

Answers

Answer:

Area total = 14.6

Step-by-step explanation:

The composite area from left to right is

a half circle plus a rectangle minus a triangle

Area total = π r²/2 + bh - 1/2(bh)

                = π (d/2)²/2 + bh - 1/2(b)(h triangle       use Pythagorean theorem

                = π (3/2)²/2 + 5(3) - 1/2(3)(√(3² - 1.5²)           h triangle = c² - (b/2)²

                = π 1.5²/2  + 15  -  1/2(3)(2.598)

Area total = 14.637 units²            

PLEASE HELP !! ILL GIVE BRAINLIEST !!

Answers

Answer:

Angles and XWY and STR

Step-by-step explanation:

These two angels are alternate exterior angels because:

- They are on different sides of the transversal (the line intersecting the two parallel lines)

- They have the same angle measure

- They are exterior, meaning they are on the outside, not inside (interior)

Hope this helps!!! :)

Help me pls I don’t get this one

Answers

Answer: <BAC is 28.5

Step-by-step explanation:

line AO and Line OB are congruent (both are radius of the circle)

<BAC and <OBA are congruent

<AOB is linear to BOC so 180-57= 123 <AOB is 123

Triangle AOB is Isosceles

2a+123=180

2a=57

a=28.5

NEED NOW WILL NAME BRAINLYIST
Determine if the three side lengths given in each problem can create a triangle or not.
a. 12 cm, 14 cm, 20 cm
b. 4 m, 8 m, 12 m
c. 23 cm, 12 cm, 13 cm

Answers

Answer:

a) yes

b) no

c) yes

Step-by-step explanation:

the sum of the 2 shorter sides must be longer than the longest side

Answer:

a and c can make a triangle.

Step-by-step explanation:

the sum of 2 sides must be greater than the last side, all the way around. so 12+14 is better than 20. but 4+8 is not better than 12

The number of miles that Kiki cycled each week for a 7-week period is shown:
36, 42, 28, 52, 48, 36, 31
What is the median number of miles Kiki cycled?

Answers

Answer:

36

Step-by-step explanation:

5th grade math. correct answer will be marked brainliest

Answers

Answer:

7/12 teaspoons

fraction

Step-by-step explanation:

Amount of salt that would be used = 1[tex]\frac{3}{4}[/tex] x [tex]\frac{1}{3}[/tex]

Convert [tex]1\frac{3}{4}[/tex] to an improper fraction

to convert to improper fraction, take the following steps :  

1. Multiply the whole number  by the denominator

2. Add the numerator to the answer gotten in the previous step

3. divide the number gotten in the previous step by the denominator

(1 x 4) + 3 = [tex]\frac{7}{4}[/tex]

7/4 x 1/3 = 7/12

Other Questions
8 OT TUWhich best describes the way poets can use end words as a device?A. End words are very noticeable, so they must represent the end of athought.B. End words stand out in poems, so they can be used to emphasizecertain elements.C. End words tend to be skipped over, so there is less pressure onthem.D. End words must rhyme, so the poet can let sound overwhelm theideas.SUBMIT Please answer help asap what factors can change the population size? A circle is given with points A, B, C, and D clockwise upon it. All points are joined by line segments, and BCD=62. What is BAD?A. 124B. 62C. 28D. 118 GIVING BRAINLIEST FOR CORRECT ANSWER SPAM AND LINKS WILL BE REPORTEDAccording to the excerpt, which of the following is the most notable change in the New South?The South has successfully diversified its industries and is selling many different products.The South has returned to an entirely agriculturally based economy.The South has fully integrated its society and is a model for how to implement the 14th Amendment.The South has successfully rebuilt its economy without any financial assistance from the North or from European nations. please help due today! Which is an example of a non-renewable resource Which of the following is true about retrospective narration?a. The narrator is describing events that are happening in the present tense.b. The narrator is predicting events that might happen in the future.c. The narrator is reflecting on events that have already happened. Which statement in the excerpt supports the idea that the author is building a slippery slope argument?adapted from Away with Standardized Testing!Standardized testing is a billion dollar industry. The companies that create these tests charge school districts and institutions millions of dollars to create and administer them. Let us not even forget the millions of dollars they make selling study guide materials for college entrance exams. Some school districts provide waivers so that students do not have to pay to take these exams. However, some students do not have that luxury and must pay for every attempt at the test until they get a desirable score. Districts are refunded when errors on these tests are discovered or when systems crash. Each year, school district funds are being reduced by states. Surely money poured into testing can be used to support other needs, such as higher teacher salaries, better school lunches, more classroom libraries, and infrastructure repairs.Sure, supporters of this dream-killing, money-sucking machine believe that standardized tests push educators to cover more content and skills and that stricter, more-aligned standardized tests ensure that students are college ready. But do these supporters stop to think about the emotional impact of standardized testing on student engagement and motivation? When students perform poorly test after test after test, not being able to gain acceptance into a college of their dreams or graduate from high school or rank highly, they are more inclined to consider dropping out of school and not pursuing college, and are more likely to tragically suffer from low self-esteem. PLEASE HELP ME 20 POINTS FIR THE CORRECT ANSWER PLEASE HELP ANSERW! WILL NAME BRANLIEST 20 POINTSSSSSSSSSSSSS!!!Lee y escoge la opcin con la palabra o palabras correctas para completar la frase. Read and choose option with the correct word or words for the blank.En ________ puedes caminar al lado del mar e ir de pesca y a veces hay montaas rusas. (1 point) ael ro bel malecn cel monumento del camping Can any one please help Which of these statements is true of plant cells?O They are prokaryotic.O They have no cell membranes.They can make their own nutrients.O They work independently of one another. what are the advantages and disadvantages of using informers Which statement best completes the diagram? Culture of Oceania. Many people are descendants of European colonists. Christianity is the most widely practiced religion.A. English is a major languageB. Musical styles are mostly EuropeanC. Dance is for bidden and a religious lawD. Most of the population lives in Micronesia How is school? Are you ok? Insects often get stuck in the sap of ancient trees. The sap along with the insect inside harden forming a fossil. What kind of fossil is this?CastCrystallizationMoldTrace In most states, economic policy is partly established byThis includes setting upexplain how money is spent. One source of revenue iswhich are collected from property, income, andother sources. Fees fromcan also be an important source of revenue. Which of these number sentences is NOT true?A. 4,000,000 millimeters =4 kilometersB. 300 millimeters >3 centimeters C. 5 meters > 5,000 millimeters D. 2,000 meters < 20 kilometers WILL GIVE BRAINLIEST FOR THE CORRECT ANSWER NO LINKS OR SPAM THEY WILL BE REPORTEDThe leaders of the group identified in question #2 aligned themselves with the: