Gribbles are small, pale white, marine worms that bore through wood. While sometimes considered a pest since they can wreck wooden docks and piers, they are now being studied to determine whether the enzyme they secrete will allow us to turn inedible wood and plant waste into biofuel.1 A sample of 50 gribbles finds an average length of 3.1 mm with a standard deviation of 0.72. Give a best estimate for the length of gribbles, a margin of error for this estimate (with 95% confidence), and a 95% confidence interval.

Answers

Answer 1

Answer:

The best estimate for the length of gribbles is of 3.1 mm.

The margin of error for this estimate, with 95% confidence, is of 0.2 mm.

The 95% confidence interval is between 2.9 mm and 3.3 mm.

Step-by-step explanation:

We have the standard deviation for the sample, which means that the t-distribution is used to solve this question.

Best estimate for the length of gribbles

The best estimate is the sample mean, that is 3.1 mm.

Margin of error:

The first step to solve this problem is finding how many degrees of freedom, we have. This is the sample size subtracted by 1. So

df = 50 - 1 = 49

95% confidence interval

Now, we have to find a value of T, which is found looking at the t table, with 49 degrees of freedom(y-axis) and a confidence level of [tex]1 - \frac{1 - 0.95}{2} = 0.975[/tex]. So we have T = 2.01

The margin of error is:

[tex]M = T\frac{s}{\sqrt{n}} = 2.01\frac{0.72}{\sqrt{50}} = 0.2[/tex]

In which s is the standard deviation of the sample and n is the size of the sample.

The margin of error for this estimate, with 95% confidence, is of 0.2 mm.

Confidence interval:

The lower end of the interval is the sample mean subtracted by M. So it is 3.1 mm - 0.2 mm = 2.9 mm

The upper end of the interval is the sample mean added to M. So it is 3.1 mm + 0.2 mm = 3.3 mm

The 95% confidence interval is between 2.9 mm and 3.3 mm.


Related Questions

The cost of 3 DVD's and 4 CD's is £62.00. The cost of 4 DVD's and 3 CD's is £64.00. Find the cost of each.
Help!!!

Answers

Answer:

the cost of each is  £10 and  £8 respectively

Step-by-step explanation:

Let us assume the cost of per DVD be x

And the cost of per CD be y

Now as per the question

The following equations should be made

3x + 4y = £62.00

4x + 3y = £64.00

Now multiply by 4 in equation 1 and 3 in equation 2

12x + 16y = £248

12x + 9y = £192

7y =  £56

y =  £8

Now put the value of y in any of the above equation

3x + 4( £8) =  £62

3x +  £32 =  £62

3x = 30

x =  £10

Hence, the cost of each is  £10 and  £8 respectively

2x - 3
M+
X + 4
X =
?

Answers

Answer:

x = 7

Step-by-step explanation:

Both equations have the same value, you have to solve for x

Let's make an equation:

2x-3   = x+4

Now you isolate one of the sides,, I will isolate the x on the first side so I will get rid of both x and 4

 2x - 3 = x + 4

-x           -x

=

x -3 = 4

Then you have to isolate x, so you add 3 on both sides

x - 3 = 4

   + 3 +3

x=7

So, the answer is x=7

Hope this helps!!

-Ketifa

Which two values are solutions of the inequality r≥6?
Select one:

r = 6, r = 9

r = −7, r = −8

r = 3, r = −10

r = 4, r = −2

Answers

Answer:

r = 6

r = 9

Step-by-step explanation:

Graph the inequality n > 1.8

Answers

Answer:

Open circle going right. <-- graphed

Step-by-step explanation:

1billion is the correct answerStep-by-step explanation:

Lina needs to write a 25-page report for homework. Last week she wrote 9 pages. She has 5 days left to finish the report. If she writes the same amount each day, about how many pages does she need to write each day to finish the report?
A. 3
B. 5
C. 2
D. 1

Answers

The correct answer is C

How many cannonballs are there in the eighth figure

Answers

Answer:

36

Step-by-step explanation:

Please need help thank you

Answers

Answer:

9

Step-by-step explanation:

Answer:

9 clients ran at least 2 laps

Step-by-step explanation:

5 clients ran 2 laps, and 4 clients ran 3 laps

Samantha wants to move into an apartment when she begins school in the fall. Right now she
has a job where she makes $250 a week working 20 hours and will be able to keep this job once
she begins school. Her parents have decided to put $500 a month in for extras that she might
need once she begins school. Although Samantha is very excited about moving into an
apartment, she wants your advice on where to begin preparing for her move. She wants to put
together a budget but has no idea where to begin.
Explain to Samantha how to set up her budget.
a
b. Once Samantha has a budget, what should she consider when determining if moving
out when she is beginning school is a good idea or not. Give specific reasons why this
might be a good or bad idea.

Answers

Answer:

she should set up a budget on how much she makes

Step-by-step explanation:

I love turtles and animals

Please help me and happy april fools day! B)

Answers

Answer:

A,C,D,F

Step-by-step explanation:

4. Identify the height of the following triangle?
A.9
B. 5
C. 4
D. 12

Answers

Answer:

if u look closely at the doted line it shows the height and the number on the inside right beside it is the height witch the answer would be C

“What is the gradient of the graph shown?”
someone please help I don’t understand how to do this.

Answers

Answer:

Step-by-step explanation:

It is easy to see that (-2, 0) and (0, -4) are points on the line.

gradient = (difference of y-coordinates)/(difference of x-coordinates) = (0-(-4))/(-2-0) = 4/(-2) =  -2

A brochure claims that the average maximum height a certain type of plant is 0.7 m. A gardener suspects that this estimate is not accurate locally due to soil conditions. A random sample of 43 plants is taken. The mean height of the plants in the sample is 0.65m. Using a 1% level of significance, perform a hypothesis test to determine whether the population mean is different from 0.7m. Assume that the population standard deviation is 0.2 m.

Answers

Answer:

We accept the null hypothesis, that is, that the population mean is not different from 0.7.

Step-by-step explanation:

A brochure claims that the average maximum height a certain type of plant is 0.7 m.

This means that the null hypothesis is:

[tex]H_{0}: \mu = 0.7[/tex]

A gardener suspects that this estimate is not accurate locally due to soil conditions.

Hypothesis test to determine whether the population mean is different from 0.7m, which means that the alternate hypothesis is:

[tex]H_{a}: \mu \neq 0.7[/tex]

The test statistic is:

[tex]z = \frac{X - \mu}{\frac{\sigma}{\sqrt{n}}}[/tex]

In which X is the sample mean, [tex]\mu[/tex] is the value tested at the null hypothesis, [tex]\sigma[/tex] is the standard deviation and n is the size of the sample.

0.7 is tested at the null hypothesis:

This means that [tex]\mu = 0.7[/tex]

A random sample of 43 plants is taken. The mean height of the plants in the sample is 0.65m.

This means, respectively, that [tex]n = 43, X = 0.65[/tex]

Assume that the population standard deviation is 0.2 m.

This means that [tex]\sigma = 0.2[/tex]

Value of the test statistic:

[tex]z = \frac{X - \mu}{\frac{\sigma}{\sqrt{n}}}[/tex]

[tex]z = \frac{0.65 - 0.7}{\frac{0.2}{\sqrt{43}}}[/tex]

[tex]z = -1.64[/tex]

Pvalue of the test:

Since we are testing that the mean is different of a value, and z is negative, the pvalue of the test is 2 multiplied by the pvalue of z = -1.64

z = -1.64 has a pvalue of 0.0505

2*0.0505 = 0.101

Using a 1% level of significance, perform a hypothesis test to determine whether the population mean is different from 0.7m.

0.101 > 0.01, which means that we accept the null hypothesis, that is, that the population mean is not different from 0.7.


x2 – 12x = 39

Please help me solve this! I need the answer ASAP

Answers

Answer:

x = 6 ± 5[tex]\sqrt{3}[/tex]

Step-by-step explanation:

Given

x² - 12x = 39

Using the method of completing the square

add ( half the coefficient of the x- term)² to both sides

x² + 2(- 6)x + 36 = 39 + 36

(x - 6)² = 75 ( take the square root of both sides )

x - 6 = ± [tex]\sqrt{75}[/tex] = ± 5[tex]\sqrt{3}[/tex] ( add 6 to both sides )

x = 6 ± 5[tex]\sqrt{3}[/tex] ← solutions in exact form

Answer:

x = 6 ± 5* OR 6 - 5*

Step-by-step explanation:

In decimal form it would be either 14.66025403... or -2.66025403

Hope this helps!

The large rectangle below represents one whole.

What percent is represented by the shaded area????

Answers

40% is shaded :))))))

Answer:

40%

Step-by-step explanation:

Because there are 5 rectangle total, we can dive 100% into 5 parts.

Each part is then 20%, there are 2 shaded rectangles thus the answer is 40%.

Whoever responds first will get marked Best!
Elizabeth's family pool is 25 feet long, 15 feet wide and 10 feet deep. The pool has to be filled. What is the volume of water they should put in the pool?
Part A Explain the steps you would take to find the volume of the pool.

Part B. What is the volume of the water in the pool?

a. 3750 ft
B.50 ft
c. 3375 ft
d. 3755 ft

Answers

Answer:

Part A:

I would multiply the length, width, and depth of the pool to find the volume of it. That would be how much water can fit inside. 25 ft x 15 ft x 10 ft = 3750 ft

Part B:

a. 3750 ft

Paleomagnetic studies of Canadian volcanic rock known as the Carmacks Group have recently been completed. The studies revealed that the northward displacement of the rock units has an approximately normal distribution with a standard deviation of 500 kilometers (Canadian Journal of Earth Sciences, Vol. 27, 1990). One group of researchers estimated the mean displacement at 1,200 kilometers, whereas a second group estimated the mean at 1,000 kilometers.

Required:
a. Assuming the mean is 1500 kilometers, what is the probability of a northward displacement of less than 500 kilometers?
b. Assuming the mean is 1200 kilometers, what is the probability of a northward displacement of less than 500 kilometers?
c. If, in fact, the northward displacement is less than 500 kilometers, which is the more plausible mean, 1200 or 1500 kilometers?

Answers

Answer:

a) 0.0228 = 2.28% probability of a northward displacement of less than 500 kilometers

b) 0.0808 = 8.08% probability of a northward displacement of less than 500 kilometers

c) 1200 kilometers, because in this case, the will be a higher probability of a northward displacement that is less than 500 kilometers.

Step-by-step explanation:

Normal Probability Distribution:

Problems of normal distributions can be solved using the z-score formula.

In a set with mean [tex]\mu[/tex] and standard deviation [tex]\sigma[/tex], the zscore of a measure X is given by:

[tex]Z = \frac{X - \mu}{\sigma}[/tex]

The Z-score measures how many standard deviations the measure is from the mean. After finding the Z-score, we look at the z-score table and find the p-value associated with this z-score. This p-value is the probability that the value of the measure is smaller than X, that is, the percentile of X. Subtracting 1 by the pvalue, we get the probability that the value of the measure is greater than X.

Standard deviation of 500 kilometers

This means that [tex]\sigma = 500[/tex]

a. Assuming the mean is 1500 kilometers, what is the probability of a northward displacement of less than 500 kilometers?

Mean of 1500 km means that [tex]\mu = 500[/tex]

The probability is the pvalue of Z when X = 500. So

[tex]Z = \frac{X - \mu}{\sigma}[/tex]

[tex]Z = \frac{500 - 1500}{500}[/tex]

[tex]Z = -2[/tex]

[tex]Z = -2[/tex] has a pvalue of 0.0228

0.0228 = 2.28% probability of a northward displacement of less than 500 kilometers.

b. Assuming the mean is 1200 kilometers, what is the probability of a northward displacement of less than 500 kilometers?

Now [tex]\mu = 1200[/tex]

[tex]Z = \frac{X - \mu}{\sigma}[/tex]

[tex]Z = \frac{500 - 1200}{500}[/tex]

[tex]Z = -1.4[/tex]

[tex]Z = -1.4[/tex] has a pvalue of 0.0808

0.0808 = 8.08% probability of a northward displacement of less than 500 kilometers.

c. If, in fact, the northward displacement is less than 500 kilometers, which is the more plausible mean, 1200 or 1500 kilometers?

1200 kilometers, because in this case, the will be a higher probability of a northward displacement that is less than 500 kilometers.

.....................help

Answers

9514 1404 393

Answer:

  -0004.00

Step-by-step explanation:

The segment has a "rise" of -4 units for the "run" of 1 unit between x=2 and x=3. Then the slope is ...

  slope = rise/run = -4/1 = -4

Please help me with this

Answers

Angle c is equal to 34 degrees. Explanation: if a=73 and b is the same as a. 73+73=146, the sum of the interior angles of a triangle is 180 degrees so 180-146= 34 degrees. Angle c is 34 degrees.

00:00

The city council in Middlefield wants to know if residents are in favor of a traffic camera at the main intersection in town. Drag tiles to match each

term to the example it best describes. Each tile may be used only once.

Representative Sample

Population

NOT a Representative Sample

Term

Example

Drivers who reside in Middlefield

Residents of Middlefield

Residents randomly chosen from the town register

Answers

Answer:

Matching Tiles with Terms:

Term                                                Example                                    

NOT a Representative Sample      Drivers who reside in Middlefield

Population                                       Residents of Middlefield            

Representative Sample                  Residents randomly chosen from the

                                                        town register

Step-by-step explanation:

Population includes all the residents of Middlefield.

Representative Sample is a population subset that accurately reflects the characteristics of the population.  For example, the subset of residents who are randomly chosen from the town register is an unbiased and representative sample.

NOT a Representative Sample: For example, drivers who reside in Middlefield do not represent the characteristics of the population of Middlefield.

After a few months, Isabella's mother decides to harvest all the peas and corn and sell it at the local market. She decides on these prices: Peas are sold at $ 3 3/4 for each square foot harvested. And, corn is sold at $ 1 1/2 for each square foot harvested. Calculate how much money she made if she sold all her produce (all of her peas and corn).

Answers

The total is $39 u can look at the pic to see how it was solve
$39 would be the total of everything


plzzzz help will
get brainliest

Answers

B, since if you plug in all of the numbers from the x side of the table you will get the numbers on the y side of the table

help me pleaseeeee !

Answers

Answer:

81 Degrees

Step-by-step explanation:

The triangles are congruent and a triangle is 180 degrees total. So, 57+42=99. 180-99=81

So the answer is 81 degrees.

Determine whether the given scenario meets the criteria of a binomial distribution. If not, identify the requirement that is not satisfied. If there is more than one requirement that is not satisfied, please indicate this by selecting the correct choice below. You ask ten randomly chosen college students to rate their experience at the dining hall on a scale of 1-5.

a. Yes, this scenario can be modeled using a binomial distribution.
b. No, there is no fixed number of trials and there are more than two possible outcomes for each trial.
c. No, there are more than two possible outcomes for each trial.
d. No, there is no fixed number of trials.

Answers

Answer:

c. No, there are more than two possible outcomes for each trial.

Step-by-step explanation:

Binomial probability distribution:

Only two possible outcomes, success or failure.

In each trial, the probability of a success must be the same.

The number of trials must be fixed.

You ask ten randomly chosen college students to rate their experience at the dining hall on a scale of 1-5.

There are 10 trials, which is a fixed number and respects the binomial distribution. However, there are five possible outcomes(numbered 1 to 5). Since there is more than two possible outcomes, the scenario cannot be modeled using a binomial distribution, and the correct answer is given by option c.

A dress is on sale for 35\% off of the regular price.

If d represents the regular price of the dress, which expression represents the sale price of the dress?


A.
0.35d

B.
0.65d

C.
1.35d

D.
1.65d

PART B
Use the information from Part A to answer the question below. The regular price of a dress is $90, determine the sale price of the dress.

The sale price of the dress is $
.

Answers

Answer:

Expression that represents the sale price of the wedding dress is  

Solution:

Given that, the dress is on sale for 35 % off the regular price

Let the regular price of dress be "w"

To find: Expression that represents the sale price of the wedding dress

Let "s" be the sale price of wedding dress

Sale price = Regular price - discount price

Discount price is given as:

Discount price = 35 % of regular price

Discount price = 35 % of w  

Thus discount price = 0.35w

Expression for the sale price of the wedding dress:

Sale price = Regular price - discount price

s = w - 0.35

s = 0.65

s= 0.65

Thus expression that represents the sale price of the wedding dress is

s=0.56

which inequality is true p=3.4

Answers

uhhh...p=3.4 is already simplified.

---

hope it helps???

9 and 11 need help
Mark brainlist

Answers

I will do 9 only. You can do 11.

Question 9

sin(60) = x/8

sin(60)(8) = x

4•sqrt{3} = x

x^2 + y^2 = 8^2

(4•sqrt{3})^2 + y^2 = 64

16(3) + y^2 = 64

48 + y^2 = 64

y^2 = 64 - 48

y^2 = 16

sqrt{y^2} = sqrt{16}

y = 4

Do 11 the same way.

-1/3*12+14=2/3*12+2=

Answers

Answer:

10=10

Step-by-step explanation:

_1(12)+14=2(12)+2

3.

When a new drug is created, the pharmaceutical company must subject it to testing before receiving the necessary permission from the Food and Drug Administration (FDA) to market the drug. Suppose the null hypothesis is "the drug is unsafe." What is the Type II Error? ( Select the one, correct letter option below) :

Answers

Answer:

Not to conclude that the drug is safe, when, in fact, it is safe.

Step-by-step explanation:

A type ii error is an error that occurs in a hypothesis testing when a person goes ahead to accept a null hypothesis when it is actually false and should be rejected.

To continue, here are the hypothesis:

H0: the drug is unsafe

H1: drug is safe.

A type ii error was committed here because H0, which is the null was accepted and it was concluded that the drug was unsafe, When in fact it should have been rejected. The conclusion should have been that the drug was safe.

In the spring of 2017, the Consumer Reports National Research Center conducted a survey of 1,007 adults to learn about their major healthcare concerns. The survey results showed that 579 of the respondents lack confidence they will be able to afford health insurance in the future. (a) What is the point estimate of the population proportion of adults who lack confidence they will be able to afford health insurance in the future. (Round your answer to two decimal places.) (b) At 90% confidence, what is the margin of error

Answers

Answer:

a) The point estimate of the population proportion of adults who lack confidence they will be able to afford health insurance in the future us 0.58.

b) The margin of error is of 0.03.

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 zscore that has a pvalue of [tex]1 - \frac{\alpha}{2}[/tex].

Point estimate:

The point estimate is [tex]\pi[/tex].

Margin of error:

The margin of error is:

[tex]M = z\sqrt{\frac{\pi(1-\pi)}{n}}[/tex]

(a) What is the point estimate of the population proportion of adults who lack confidence they will be able to afford health insurance in the future.

579 out of 1007 adults. So

[tex]\pi = \frac{579}{1007} = 0.575[/tex]

Rounding to two decimal places, 0.58

The point estimate of the population proportion of adults who lack confidence they will be able to afford health insurance in the future us 0.58.

(b) At 90% confidence, what is the margin of error

90% confidence level

So [tex]\alpha = 0.1[/tex], z is the value of Z that has a pvalue of [tex]1 - \frac{0.1}{2} = 0.95[/tex], so [tex]Z = 1.645[/tex].

The margin of error is:

[tex]M = z\sqrt{\frac{\pi(1-\pi)}{n}}[/tex]

[tex]M = 1.645\sqrt{\frac{0.58*0.42}{1007}}[/tex]

[tex]M = 0.03[/tex]

The margin of error is of 0.03.

Write an equation and solve for the missing anglemeasure.

Equation: _______________________

Angle g = ___________

Answers

Answer:

Equation: [tex]143 + g = 180[/tex]

[tex]g =37[/tex]

Step-by-step explanation:

Given

The attached figure

Required

The equation to find g and the solution

From the attached: Angles ACD, DCE and ECB lie on a straight line.

Where

[tex]ACD = 90[/tex]       [tex]DCE = 53[/tex]     [tex]ECB = g[/tex]

This means that:

[tex]ACD + DCE + ECB = 180[/tex]

[tex]90 + 53 + g = 180[/tex]

[tex]143 + g = 180[/tex]

Subtract 143 from both sides

[tex]-143 + 143 + g = 180 - 143[/tex]

[tex]g = 37[/tex]

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Select the statement that can be represented by -10 dollars. The radius of the base of a metallic rod is 2 centimeters, and its height is 15 centimeters. What is the volume of this cylinder? A.60 cm^3 B.50 cm^3 C.27 cm3 D.36 cm^3 Write 16 exponentially two different ways help me Please help me please help me please help me please What is the best anime.(your opinion) If mT = (2x + 85) , mV = (5x + 29) , and the sum of the measures of the angles is 93 , find the measure of each angle. Describe the 6 phases of developing a vaccine Look at the image and read the trailer.Which best describes the tone of this trailer?chaotictranquilmysteriousrelaxed ASAP due today Explain one challenge we face using nuclear energy. Derive, with full working, the symbol equation for the power output P watts of the energy transfer that occurs when a mass of m kg falls through a height of h metres in t seconds. A loan of$8000 was repaid in 24 equal monthly installments of $400 . The rate of interest on the loan was Saraid is dividing 14 pound of cashews into 5 plastic bags. What fraction of a pound of cashews will be in each plastic bag? Calculate the missing angle measure of each triangle on the left butterfly wing. Write the angle measure inside the angle. The right butterfly wing is a reflection of the left butterfly wing and corresponding angles are congruent. Which is the most likely effect of an allusion that is too dramatic for thecontext?A. The reader will be able to picture the scene.B. The reader will be impressed.C. The reader will feel strong emotions.D. The reader will not take it seriously. Find the slope of the line that passes through each pair of points.A(-6,1) B(2,1) Some hoodlums who have been earning money by stealing copper pipes and cable and selling them to recyclers are driving around one evening when they spot an unattended strange-looking building sitting out in the middle of a field, break in, and steal all of the copper wire they can haul in their truck, disabling the VOR air navigation facility. Required:In addition to trespassing, breaking and entering, and burglary, have they committed any aviation-specific federal crimes? If so, identify each such crime(s) and describe the penalties. What are cartographers?A)journalist who specifically write about geographic disputesB)city plannersC)map makersD)symbolic representations of space Which of the following is true of the composition of all materials? A. All materials are made up of large parts that can only be seen by the human eye. B. All materials are made up of smaller parts that cannot be seen without magnification. C. All materials are made up of living cells. D. All materials are made up of only one part. solve 3(2x + 1) in standard form 2x - 3M+X + 4X =?