You are at a playground with a see-saw and a large merry-go-round. You put your phone on the see-saw and find it slides when it is tilted at an angle of 38 degrees. How far can you put your phone from the center of the merry-go-round (in m) when it makes one rotation every 3 s

Answers

Answer 1

Answer:  r_max = 1.75m

Step-by-step explanation:

Below is a rather brief analysis to solving this problem.

The phone starts sliding when along incline,

when F_net = m g sin(theta) - fs_max = 0  

and fs_max = us N = us m g cos(theta)

m g sin(theta) - us m g cos(theta) =

us = tan(theta) = tan38 = 0.781  

On merry - go - round,

fs_max = us N = us m g

Using F = m a

fs_max = m w^2 r_max and w = 2pi / T

us m g = m (2 pi / T)^2 (r_max)

0.781 x 9.81 = (2 pi / 3)^2 (r_max)

r_max = 1.75 m

cheers i hope this helped !!


Related Questions

Steve wants to use his 18% employee discount to buy a video game that has a regular price of $69.99. A 6.5% sales tax is applied to the discounted price. How much will he pay for the game, including sales tax?

Answers

Answer:

$61.12

Step-by-step explanation:

Price of the Video game = $69.99

Discount = 18%

Discount price = 18% of $69.99

                         = $69.99*18/100

                         = $12.6

Price after Discount = Price - Discount price

                                  = $69.99 - $12.6

                                  = $57.39

Sales tax = 6.5% applied to the discounted price

                = 6.5% of $57.39

sales tax in dollars = $57.39 * 6.5/100

                               = $3.73

The amount he pays for the game = $57.39 + $3.73

                                                          = $61.12

What’s 148+383-163=?

Answers

Answer:

368

Step-by-step explanation:

What term should be inserted in
p²-
___+36 to make it a perfect
Square​

Answers

Answer:

12p

Step-by-step explanation:

the perfect square is form

(p - 6)² = p² - 12p + 36

Answer:

12p

Step-by-step explanation:

p² - ? + 36 = p² - ? + (-6)² = p² -2*6*p + (-6)² = p² - 12p + 36 = (p-6)²

One third of the sum of 15
and thrice a certain number is
equal to twice the number. Find
the number​

Answers

Answer:

x=-1/39

Step-by-step explanation:

3km 5hm multiplied by 15 equals what

Answers

Answer: 525

Step-by-step explanation:

3 km =30 hm

35hm*15=525

A standardized​ exam's scores are normally distributed. In a recent​ year, the mean test score was 1521 and the standard deviation was 314. The test scores of four students selected at random are 1920​, 1290​, 2220​, and 1420. Find the​ z-scores that correspond to each value and determine whether any of the values are unusual

Answers

Answer:

A score of 1920 has a z-score of 1.27.

A score of 1290 has a z-score of -0.74.

A score of 2220 has a z-score of 2.23.

A score of 1420 has a z-score of -0.32.

The score of 2220 is more than two standard deviations from the mean, so it is unusual.

Step-by-step explanation:

When the distribution is normal, we use 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.

If X is 2 or more standard deviations from the mean, it is considered unusual.

In this question, we have that:

[tex]\mu = 1521, \sigma = 314[/tex]

Score of 1920:

X = 1920. Then

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

[tex]Z = \frac{1920 - 1521}{314}[/tex]

[tex]Z = 1.27[/tex]

A score of 1920 has a z-score of 1.27.

Score of 1290:

X = 1290. Then

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

[tex]Z = \frac{1290 - 1521}{314}[/tex]

[tex]Z = -0.74[/tex]

A score of 1290 has a z-score of -0.74.

Score of 2220:

X = 1290. Then

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

[tex]Z = \frac{2220 - 1521}{314}[/tex]

[tex]Z = 2.23[/tex]

A score of 2220 has a z-score of 2.23.

Since it is more than 2 standard deviations of the mean, the score of 2220 is unusual.

Score of 1420:

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

[tex]Z = \frac{1420 - 1521}{314}[/tex]

[tex]Z = -0.32[/tex]

A score of 1420 has a z-score of -0.32.

Write the ratio 70:80 in its simplest form

Answers

Answer:

7/8!

Step-by-step explanation:

They both can be divided by 10, so do just that. Then you are left with 7/8 which cannot be simplified.

The ratio 70:80 in its simplest form is equal to 7:8.

To simplify the ratio 70:80, we need to find the greatest common divisor (GCD) of the two numbers and then divide both numbers by the GCD.

Step 1: Find the GCD of 70 and 80:

The factors of 70 are 1, 2, 5, 7, 10, 14, 35, and 70.

The factors of 80 are 1, 2, 4, 5, 8, 10, 16, 20, 40, and 80.

The common factors of 70 and 80 are 1, 2, 5, and 10. The greatest common divisor (GCD) is 10.

Step 2: Divide both numbers by the GCD (10):

70 ÷ 10 = 7,

80 ÷ 10 = 8.

In summary, the ratio 70:80 can be simplified by dividing both numbers by their greatest common divisor (GCD), which is 10. After simplification, the ratio becomes 7:8. Simplifying ratios involves dividing both parts of the ratio by the greatest common factor to express the ratio in its simplest and most concise form.

This makes it easier to understand and work with the relationship between the quantities being compared. In this case, the simplified ratio tells us that for every 7 units of the first quantity, there are 8 units of the second quantity.

To learn more about ratio click on,

https://brainly.com/question/14636942

#SPJ2

A man is giving a dinner party. His current wine supply includes 8 bottles of zinfandel, 10 of merlot, and 12 of cabernet, all from different wineries. a) If he wants to serve 3 bottles of zinfandel and serving order is important, how many ways are there to do this? (2 points) b) If 6 bottles are randomly selected, what is the probability that this results in two bottles of each variety being chosen? (4 points) c) If 6 bottles are randomly selected, what is the probability that all of them are the same variety?

Answers

Answer:

a. 336

b. 14.01%

c. 0.2%

Step-by-step explanation:

a. We have that the number of zinfandel bottles is 8 and that the number of zinfandel served is 3, therefore:

n = 8 and r = 3

we can calculate it by means of permutation:

nPr = n! / (n-r)!

replacing:

8P3 = 8! / (8-3)!

8P3 = 336

Which means there are 336 ways.

b. First we must calculate the ways to choose 2 bottles of each variety, through combinations:

nCr = n! / (r! * (n-r)!

We know that there are 8 bottles zinfandel, 10 of merlot, and 12 of cabernet, and we must choose 2 of each, therefore it would be:

8C2 * 10C2 * 12C2

8! / (2! * (8-2)! * 10! / (2! * (10-2)! * 12! / (2! * (12-2)!

28 * 45 * 66 = 83160

Now we must calculate the total number of ways, that is, choose 6 bottles of the 30 total (8 + 10 + 12)

30C6 = 30! / (6! * (30-6)! = 593775

Thus:

83160/593775 = 0.1401

In other words, the probability is 14.01%

c. In this case, we must calculate the number of ways of 8 bottles zinfandel, 10 of merlot, and 12 of cabernet choose 6, that is to say that they are all of the same variety, therefore:

8C6 + 10C6 + 12C6

8! / (6! * (8-6)! + 10! / (6! * (10-6)! + 12! / (6! * (12-6)!

28 + 210 + 924 = 1162

And that divide it by the total amount that we calculated the previous point, 30C6 = 593775

Thus:

1162/593775 = 0.002

In other words, the probability 0.2%

How many solutions does the system have? y = -2x-4 \\\\ y = 3x+3

Answers

Answer:

The system has one solution.

Step-by-step explanation:

We have two equations:

y = -2x - 4

y = 3x + 3

Equalling them:

y = y

-2x - 4 = 3x + 3

5x = -7

[tex]x = -\frac{7}{5}[/tex]

And

[tex]y = 3x + 3 = 3(-\frac{7}{5}) + 3 = \frac{-21}{5} + 3 = \frac{-21}{5} + \frac{15}{5} = -\frac{6}{5}[/tex]

Replacing in the other equation we should get the same result.

[tex]y = -2x - 4 = -2(-\frac{7}{5}) - 4 = \frac{14}[5} - 4 = \frac{14}{4} - \frac{20}{5} = -\frac{6}{5}[/tex]

So the system has one solution.

If someone have all the proofs of this I’ve been trying since yesterday PLEASE

Answers

Answer:

Please see steps below

Step-by-step explanation:

Notice the following:

(a) Angles 5 and 1 are alternate angles between parallel lines, and then they must be congruent (equal in measure)  [tex]\angle 1 \,=\,\angle 5[/tex]

(b) Angles 6 and 3 are also alternate angles  between parallel lines, so they must be congruent (equal measure)  [tex]\angle 3 \,=\,\angle 6[/tex]

Therefore, instead of expressing the addition:

[tex]\angle 5\,\,+\,\,\angle 2\,\,+\,\,\angle 6[/tex]

we can write:

[tex]\angle 1\,\,+\,\,\angle 2\,\,+\,\,\angle 3[/tex]

which in fact clearly add to [tex]180^o[/tex]

Suppose the labor force is 189 million of a possible 244 million working-age adults. The total number of unemployed is 15 million. What
is the standard unemployment rate?

Answers

Answer:

The standard unemployment rate is of 0.0794 = 7.94%.

Step-by-step explanation:

The standard unemployment rate, as a proportion, is the number of unemployed people divided by the size of the labor force.

In this question:

Labor force: 189 million

Number of unemployed people: 15 million

What is the standard unemployment rate?

15/189 = 0.0794

The standard unemployment rate is of 0.0794 = 7.94%.

Which expression is equivalent to 36 a minus 27?
9 (4 a minus 3)
3 (18 a minus 9)
9 (4 a minus 27)
3 (12 a minus 6)

Answers

Answer:

[tex]9(4a)-9(3)[/tex]

Step-by-step explanation:

[tex]36a-27[/tex]

[tex]9(4a)-9(3)[/tex]

[tex]9(4a-3)[/tex]

Answer:

it is 9(4a-3)

Step-by-step explanation:

Please help me explain your answer only answer if you are sure

Answers

Answer:

The answer of top prism is 262

and down prism is 478

The upper figure is triangular prism.

so, we use bh+2ls+lb formula

B=5

h=3

s=4

l=19

Now,

surface area of triangular prism = bh+2ls+lb

= 5×3+2×19×4+19×5

= 262

The down figure is rectangular prism.

so, we use 2lw+2lh+2hw

l=5

h=6

w=19

Now,

The area of rectangular prism = 2lw+2lh+2hw

= 2×5×19+2×19×6+2×5×6

= 478

Answer on top is prism 262

You are choosing between two different window washing companies. The first charges $5 per window. The second charges a base fee of $40 plus $3 per window

Answers

Answer:

you forgot the rest of the question homie but once there is 20 companies both companies will be equal

Step-by-step explanation:

Answer:

20 windows

Step-by-step explanation:

The longer leg of a 30-60-90° triangle is 18. What is the length of the other leg?
A) 1213
B) 93
C) 9
D) 63

Answers

Answer:

D

Step-by-step explanation:

In a 30-60-90 triangle, the longer leg is [tex]\sqrt{3}[/tex] times larger than the smaller leg. The length of the shorter leg is therefore:

[tex]\dfrac{18}{\sqrt{3}}= \\\\\\\dfrac{18\sqrt{3}}{3}= \\\\\\6\sqrt{3}[/tex]

Hope this helps!

6
Cheryl had 160 stickers more than Gareth. If Cheryl gave 185 stickers
to Gareth, Gareth would have 3 times as many stickers as Cheryl
How many stickers did Gareth have at first?
165​

Answers

Answer:

260 stickers

Step-by-step explanation:

Let Gareth's stickers be x.

Hence Cheryl sticker is 160+x;

If Cheryl gave 185 stickers

to Gareth, it means:

Cheryl has at the moment;

160 + x - 185 = x - 25

At this time when Gareth receives 185 he now has:

x+ 185

Also when he receives x +185, he has 3 times Cherry's meaning:

x+185 =3(x-25)

x + 185 = 3x -75

185 + 75 = 3x-2x

260= x

x = 260.

Hence Gareth has 260 stickers

Which of the following functions is graphed below

Answers

Answer:

B

Step-by-step explanation:

Find the quotient
-99 over -11

Answers

Answer:

the quotient is 9 because a negative divided by a negative is a positive

The answer is "A"
"negative number divide with negative number result in positive number"​
-99/-11=9

if jm = 5x - 8 and lm = 2x - 6, which expression represents jl

Answers

Answer:

7x -14 = jl

Step-by-step explanation:

Assuming a straight line

jm+ ml = jl

5x-8 + 2x-6 = jl

Combine like terms

7x -14 = jl

7x-14=jl assuming a straight line

g Using a calculator, find the actual error in measuring volume if the radius was really 6.5 cm instead of 6 cm, and find the actual error if the radius was actually 5.5 cm instead of 6 cm. Compare these errors to the answer you got using differentials

Answers

Answer:

The answer is "[tex]58.625 cm^3[/tex]"

Step-by-step explanation:

Consider the cube volume of x =6 cm.

Substitute x = 6 cm in the volume

[tex]V= x^3\\\\ V = (6)^3\\\\ V = 216[/tex]

Therefore, whenever the cube volume

[tex]x=6 \ cm \ is \ V= 216 \ cm^3[/tex]

Then consider the cube's volume

x = 6.5 cm.

Substitute x = 6.5 cm in the volume

[tex]V_1 = x^3\\V_1 = (6.5)^3\\V_1 = 274.625 \\[/tex]   by using the calculator.

Therefore, when another cube volume

[tex]x = 6.5 cm \\\\ V_1 = 274.625 cm^3.[/tex]

The real volume error x = 6.5 cm instead of x = 6 cm is calculated as,

[tex]dV= V_1-V\\[/tex]

     [tex]=274.625-216\\=58.625\\[/tex]

Hence, the actual error in the volume when x = 6.5 cm instead of x = 6 cm is [tex]58.625 \ cm^3.[/tex]

Environmental Protection Agency standards require that the amount of lead in drinking water be less than 15 ppb. Twelve samples of water from a particular source have the following concentrations, in ppb. 11.4 13.9 11.2 14.5 15.2 8.1 12.4 8.6 10.5 17.1 9.8 15.9 A hypothesis test will be performed to determine whether the water from this source meets the EPA standard.

Required:
a. State the appropriate null and alternate hypotheses.
b. Compute the P-value.
c. Can you conclude that the water from this source meets the EPA standard? Explain.

Answers

Answer:

Step-by-step explanation:

Mean = (11.4 + 13.9 + 11.2 + 14.5 + 15.2 + 8.1 + 12.4 + 8.6 + 10.5 + 17.1 + 9.8 + 15.9)/12 = 12.4

Standard deviation = √(summation(x - mean)²/n

n = 12

Summation(x - mean)² = (11.4 - 12.4)^2 + (13.9 - 12.4)^2 + (11.2 - 12.4)^2+ (14.5 - 12.4)^2 + (15.2 - 12.4)^2 + (8.1 - 12.4)^2 + (12.4 - 12.4)^2 + (8.6 - 12.4)^2 + (10.5 - 12.4)^2 + (17.1 - 12.4)^2 + (9.8 - 12.4)^2 + (15.1 - 12.4)^2 = 89.62

Standard deviation = √(89.62/13) = 2.7

We would set up the hypothesis test. This is a test of a single population mean since we are dealing with mean

a) For the null hypothesis,

µ ≤ 15

For the alternative hypothesis,

µ > 15

This is a right tailed test

b) Since the number of samples is small and no population standard deviation is given, the distribution is a student's t.

Since n = 12,

Degrees of freedom, df = n - 1 = 12 - 1 = 11

t = (x - µ)/(s/√n)

Where

x = sample mean = 12.4

µ = population mean = 15

s = samples standard deviation = 2.7

t = (12.4 - 15)/(2.7/√12) = - 3.34

We would determine the p value using the t test calculator. It becomes

p = 0.0034

c) Assuming level of significance = 0.05.

Since alpha, 0.05 > than the p value, 0.0034, then we would reject the null hypothesis. Therefore, At a 5% level of significance, we can conclude that the water from this source does meets the EPA standard. They are higher than 15ppb

Using the t-distribution, we have that:

a)

The null hypothesis is: [tex]H_0: \mu \geq 15[/tex]

The alternative hypothesis is: [tex]H_1: \mu < 15[/tex]

b) The p-value is of 0.0051.

c) Since the p-value is of 0.0051, which is less than the standard significance level of 0.0051, it can be concluded that the mean is less than 15 ppb, and thus, this source meets the EPA standard.

Item a:

At the null hypothesis, it is tested if the mean is of at least 15 ppb, that is:

[tex]H_0: \mu \geq 15[/tex]

At the alternative hypothesis, it is tested if the mean is of less than 15 ppb, that is:

[tex]H_1: \mu < 15[/tex]

Item b:

We have the standard deviation for the sample, thus, the t-distribution is used. The test statistic is given by:

[tex]t = \frac{\overline{x} - \mu}{\frac{s}{\sqrt{n}}}[/tex]

The parameters are:

[tex]\overline{x}[/tex] is the sample mean. [tex]\mu[/tex] is the value tested at the null hypothesis. s is the standard deviation of the sample. n is the sample size.

In this problem, we have that [tex]\mu = 15, n = 12[/tex]. Additionally, using a calculator, the other parameters are: [tex]\overline{x} = 12.38, s = 2.93[/tex]

Hence, the value of the test statistic is:

[tex]t = \frac{\overline{x} - \mu}{\frac{s}{\sqrt{n}}}[/tex]

[tex]t = \frac{12.38 - 15}{\frac{2.93}{\sqrt{12}}}[/tex]

[tex]t = -3.1[/tex]

The p-value is found using a left-tailed test, as we are testing if the mean is less than a value, with t = -3.1 and 12 - 1 = 11 df.

Using a calculator, this p-value is of 0.0051.

Item c:

Since the p-value is of 0.0051, which is less than the standard significance level of 0.0051, it can be concluded that the mean is less than 15 ppb, and thus, this source meets the EPA standard.

A similar problem is given at https://brainly.com/question/16194574

A hospital claims that the proportion, , of full-term babies born in their hospital that weigh more than pounds is . In a random sample of babies born in this hospital, weighed over pounds. Is there enough evidence to reject the hospital's claim at the

Answers

Complete question is:

A hospital claims that the proportion, p, of full-term babies born in their hospital that weigh more than 7 pounds is 36%. In a random sample of 170 babies born in this hospital, 56 weighed over 7 pounds. Is there enough evidence to reject the hospital's claim at the level of significance?

Answer:

Yes, there is enough evidence to reject the claim.

Step-by-step explanation:

We are given;

n = 170

x = 56

So, will use one sample proportion test to solve this.

p^ = x/n

p^ = 56/170

p^ = 0.3294

Since the proportion, p, of full-term babies born in their hospital that weigh more than 7 pounds is 36%.

Thus;

Null Hypothesis H0: p ≠ 0.36

Alternative Hypothesis Ha: p = 0.36

Formula for test statistic = (p^ - p)/√(p(1 - p)/n)

This gives;

Test statistic = (0.3294 - 0.36)/√(0.36(1 - 0.36)/170)

Test statistic = -0.8311

From z-table and online z-calculator, the p - value is 0.203.

level of significance is; α = 0.05

Now, Since the p value < α, we reject the null hypothesis .

Thus, the claim is true

In the circle below, CD is a diameter. If AE=10, CE=4, and AB=16, what is
the length of the radius of the circle?
Please Help ASAP

Answers

Answer:

(D)9.5 Units

Step-by-step explanation:

We have two chords CD and AB intersecting at E.

Using the theorem of intersecting chords

AE X EB =CE X ED

AE=10CE=4AB=16

AB=AE+EB

16=10+EB

EB=16-10=6

Therefore:

AE X EB =CE X ED

10 X 6 = 4 X ED

ED =60/4 =15

Therefore:

CD=CE+ED

=4+15

CD=19

Recall that CD is a diameter of the circle and;

Radius =Diameter/2

Therefore, radius of the circle =19/2 =9.5 Units

How long is a average teen suppose to be

Answers

Answer:

The way adolescents spend their time can strongly influence their health later in life. For youth to maintain a healthy future, they need plenty of sleep; good nutrition; regular exercise; and time to form relationships with family, friends, and caring adults. Additionally, the time adolescents spend in school and in after-school activities with peers and adults can advance healthy academic, emotional, social, and physical development. The amount of time they spend on screens and in social media may also influence adolescents’ overall well-being.

The American Time Use Survey, collected by the U.S. Bureau of Labor Statistics, contains detailed information about how individuals ages 15 and older use their time and provides a picture of a typical weekday and weekend day for a high school teen during the school year. Here we specifically analyze how adolescents ages 15-19 who are enrolled in high school spend their time.

Step-by-step explanation:

Find the median of the data in the dot plot below.

Answers

The value of the median is 25 from the dot plot because the middle value is 25 on the dot plot,

What is the median?

A median is a middle number in a series of numbers that have been arranged to lift, and it might be more informative of the set of data than the average. When there are extremes in the sequences that might affect the average of the numbers, the median is sometimes employed instead of the mean.

We have a dot plot shown in the picture.

As we can see in the dot plot there are a total of 9 dots.

4 dots left side and 4 dots right side.

One dot is left which is pointing to the value 25 at the number line.

Thus, the value of the median is 25 from the dot plot because the middle value is 25 on the dot plot,

Learn more about the median here:

brainly.com/question/21396105

#SPJ1

Harasti was inspired to build his hotels after he saw seahorses living in old fishing traps. What is the volume of a fishing trap that is 2 feet wide, 5 feet long, and 3 feet tall?

HELP ME DO THIS !!!!

Answers

Answer:

volume of rectangular prism = 30 ft³

Step-by-step explanation:

The fishing trap he wants to build to house sea houses are mostly rectangular prism. The traps are mostly glass like. The volume of the fishing trap will be the volume of the rectangular prism.

volume of rectangular prism = LWH

where

L = length

W = width

H = height

volume of rectangular prism = LWH

Length = 5 ft

width = 2 ft

Height = 3 ft

volume of rectangular prism = 5 × 2 × 3

volume of rectangular prism = 10 × 3

volume of rectangular prism = 30 ft³

This chart shows Dan’s budget:

A 3-column table has 5 rows. The first column is labeled Item with entries Internet, food, rent, discretionary spending, income. The second column is labeled Amount budgeted with entries 35, 100, 500, 100, 750. The third column is labeled Amount spent with entries 35, 95, 500, 140, blank.

Did Dan stay on budget? Why or why not?

Yes, Dan spent as much as he earned.
No, Dan should move to a new apartment.
Yes, Dan uses his savings to cover extra expenses.
No, Dan should reduce his discretionary spending

Answers

The correct answer is D No, Dan should reduce his discretionary spending

Explanation:

For Dan to stay on the budget he needs to spend the amount budgeted for each expense or less than the amount budgeted. This occurred in the case of the Internet, food, and rent; for example, the amount budgeted for the internet was $35 and Dan spent this money, also, the amount budgeted for food was $100 and Dan spent $95, which means he stood in the budget. However, this did not occur with discretionary spending, which refers to other non-necessary expenses, because in this case, Dan spent $140 even when the budget limit was $100. Also, this exceeds the total income considering 35 + 95 + 500+ 140 = $770, which is above the income ($750). Thus, Dan did not stay in the budget because he spent more money than expected in discretionary spending and should reduce this.

The correct answer is D. No, Dan should reduce his discretionary spending.

Hope this helps

:)

Solve the equation then write how many solutions there is in this problem: 8x-3+14=24x+5

Answers

Answer:

x = 0.375

Step-by-step explanation:

Step 1: Simplify both sides of the equation

8x − 3 + 14 = 24x + 5

(8x) + (−3 + 14) = 24x + 5

8x + 11 = 24x + 5

- 24

-16x + 11 = 5

-11

-16x = -6

-16x/-16 = -6/-16

x = 3/8

x = 0.375

The manufacturer of a smart watch claims that individuals who pay attention to how many steps they take per day will inadvertently take more steps per day than individuals who pay no attention to how many steps they take per day. To investigate this claim, the manufacturer conducts a study to estimate the difference in the mean number of steps taken by those that pay attention to how many steps they take per day and those that do not. To do so, 40 volunteers are recruited. Half of the volunteers are randomly assigned to receive a smart watch and are taught how to use it to track their steps. The other half of the volunteers are given a wristband to wear, but are not informed that the wristband is tracking their steps. The volunteers are monitored for 30 days. The mean and standard deviation of the number of steps taken per day are computed for each group. Here are the data:
Payti
Do not pay itin 01 0 10 20 87 64 82 350
Which of the following is a 99% confidence interval for the difference in the mean number of steps taken by all people like these that do and do not pay attention to the number of steps they take per day using df - 192
(A) 1596 + 2.861/15802 + 23502
(B) 1596 +2.861, 15.302 – 23502
(C) 1596 +2.576,15802 + 23502
(D) 1596 + 2.576 ( 15802 + 23502) °
(E) 1596 + 2.576 ( 15892 – 23502)

Answers

Here is the correct question.

The manufacturer of a smart watch claims that individuals who pay attention to how many steps they take per day will inadvertently take more steps per day than individuals who pay no attention to how many steps they take per day. To investigate this claim, the manufacturer conducts a study to estimate the difference in the mean number of steps taken by those that pay attention to how many steps they take per day and those that do not. To do so, 40 volunteers are recruited. Half of the volunteers are randomly assigned to receive a smart watch and are taught how to use it to track their steps. The other half of the volunteers are given a wristband to wear, but are not informed that the wristband is tracking their steps. The volunteers are monitored for 30 days. The mean and standard deviation of the number of steps taken per day are computed for each group. Here are the data:

                                           [tex]n[/tex]                     [tex]\bar x[/tex]                  [tex]S_x[/tex]

Pay attention                    20                 10,244            1,580

Do not pay attention        20                 8.,648            2,350

Which of the following is a 99% confidence interval for the difference in the mean number of steps taken by all people like these that do and do not pay attention to the number of steps they take per day using df - 19 ?

[tex](A) \ 1596 \ \pm 2.861 \sqrt{ \dfrac{1580^2}{20} + \dfrac{2350^2}{20}} \\ \\ \\ (B) \ 1596 \ \pm 2.861 \sqrt{ \dfrac{1580^2}{20} - \dfrac{2350^2}{20}} \\ \\ \\ (C) \ 1596 \pm 2.576 \sqrt{ \dfrac{1580^2}{20} + \dfrac{2350^2}{20}} \\ \\ \\ (D) 1596 \pm 2.576 ( \dfrac{1580^2}{\sqrt{20}} + \dfrac{2350^2}{\sqrt{20}}) \\ \\ \\ (E) 1596 \pm 2.576 ( \dfrac{1580^2}{\sqrt{20}} - \dfrac{2350^2}{\sqrt{20}})[/tex]

Answer:

[tex]\mathbf{(A) \ 1596 \ \pm 2.861 \sqrt{ \dfrac{1580^2}{20} + \dfrac{2350^2}{20}}}[/tex]

Step-by-step explanation:

Given that :

significance level [tex]\alpha = \mathbf{0.01}[/tex]

From the Given data;

Using Excel with the function : TINV(0.01,19);

Critical value t* = 2.861

The margin of error can now be represented by the illustration:

Margin of error = [tex]t^* \sqrt{ \dfrac {s_1 ^2}{n_1} + \dfrac {s_2 ^2}{n_2}[/tex]

Lower Limit =  [tex](\bar x_1 - \bar x_2)- (Margin \ of \ error)[/tex]

Upper Limit =  [tex](\bar x_1 - \bar x_2)+ (Margin \ of \ error)[/tex]

Thus; the confidence interval for the difference in the mean number of steps taken by all people like these that do and do not pay attention to the number of steps they take per day using df - 19 is:

[tex]\mathbf{(A) \ 1596 \ \pm 2.861 \sqrt{ \dfrac{1580^2}{20} + \dfrac{2350^2}{20}}}[/tex]

A ball is thrown downward from the top of a 240​-foot building with an initial velocity of 20 feet per second. The height of the ball h in feet after t seconds is given by the equation h= -16t^2 - 20t + 240. How long after the ball is thrown will it strike the​ ground?

Answers

Answer:

3.29 s

Step-by-step explanation:

We are given that

Height of building=240

Initial velocity=20ft/s

The height of the ball  after t seconds is given by

[tex]h(t)=-16t^2-20t+240[/tex]

When the ball strike the ground then

h(t)=0

[tex]-16t^2-20t+240=0[/tex]

[tex]4t^2+5t-60=0[/tex]

Quadratic formula:

[tex]x=\frac{-b\pm\sqrt{b^2-4ac}}{2a}[/tex]

Using the quadratic formula

[tex]t=\frac{-5\pm\sqrt{25+960}}{8}[/tex]

[tex]t=\frac{-5\pm\sqrt{985}}{8}[/tex]

[tex]t=\frac{-5+31.28}{8}=3.29 s[/tex]

[tex]t=\frac{-5-31.38}{8}=-4.5[/tex]

Time cannot be negative .Therefore,

t=3.29 s

Other Questions
Multiple-step income statement and balance sheet The following selected accounts and their current balances appear in the ledger of Kanpur Co. for the fiscal year ended June 30, 20Y7: Cash $92,000 Retained Earnings $381,000Accounts Receivable 450,000 Dividends 300,000Inventory 370,000 Sales 8,925,000Estimated Returns Inventory 5,000 Cost of Goods Sold 5,620,000Office Supplies 10,000 Sales Salaries Expense 850,000Prepaid Insurance 12,000 Advertising Expense 420,000Office Equipment 220,000 Depreciation ExpenseStore Equipment 33,000Accumulated DepreciationOffice Equipment 58,000 Miscellaneous Selling Expense 18,000Store Equipment 650,000 Office Salaries Expense 540,000Accumulated DepreciationStore Equipment 87,500 Rent Expense 48,000Accounts Payable 38,500 Insurance Expense 24,000Customers Refunds Payable 10,000 Depreciation ExpenseOffice Equipment 10,000Salaries Payable 4,000 Office Supplies Expense 4,000Note Payable (final payment due 2034) 140,000 Miscellaneous Administrative Exp. 6,000Common Stock 50,000 Interest Expense 12,000Required:a. Prepare a multiple-step income statement.b. Prepare a retained earnings statement. What is the dominant form of sound repetition in this line from "The Fish"? with the swivel still attachedSelect the best answer from the choices provided.A. consonanceB. assonanceC. alliterationD. rhyme a slushy machine fills 25 containers that hold 64 oz of liquid in a day. how many quarts is this? 6Cheryl had 160 stickers more than Gareth. If Cheryl gave 185 stickersto Gareth, Gareth would have 3 times as many stickers as CherylHow many stickers did Gareth have at first?165 What does Macbeth see on his way to kill Duncan? From an upstairs window, I can see my neighbor's fence. The angle of depression is 7 degrees. If my window is 15 ft off the ground, how far is my neighbor's fence from my house? Round to the nearest whole number, do not include units. *Its not 17 or 1.8 I have tried and those are wrong Find the quotient -99 over -11 What should a person wear during a sports activity? Whats 148+383-163=? Trina examined the equation below and said that the equation has exactly one solution. Negative 8 (x minus 4) + 2 x = negative 4 (x minus 8) minus 2 x Which explains whether Trina is correct? A. Trina is correct because the two sides of the equation are equivalent. B. Trina is correct because the two sides of the equation are not equivalent. C. Trina is not correct because the two sides of the equation are equivalent. D. Trina is not correct because the two sides of the equation are not equivalent. The radius of a circle is 7m. Find the circumference to the nearest tenth(urgent) Plz I need help, I'm confused. What inference can be made based on the following sentence: Eventually, the drachma use declined as foreign powers took over the region? Mitchell's family is slow cooking 2 3/4 pounds of meat. The recipe says to cook the meat 1 1/2 nours per pound,How long should Mitchell's family cook the meat?A 1 5/6B. 2 3/8 C 4 1/ 8 D. 4 1/4 The manufacturer of a smart watch claims that individuals who pay attention to how many steps they take per day will inadvertently take more steps per day than individuals who pay no attention to how many steps they take per day. To investigate this claim, the manufacturer conducts a study to estimate the difference in the mean number of steps taken by those that pay attention to how many steps they take per day and those that do not. To do so, 40 volunteers are recruited. Half of the volunteers are randomly assigned to receive a smart watch and are taught how to use it to track their steps. The other half of the volunteers are given a wristband to wear, but are not informed that the wristband is tracking their steps. The volunteers are monitored for 30 days. The mean and standard deviation of the number of steps taken per day are computed for each group. Here are the data: Payti Do not pay itin 01 0 10 20 87 64 82 350 Which of the following is a 99% confidence interval for the difference in the mean number of steps taken by all people like these that do and do not pay attention to the number of steps they take per day using df - 192 (A) 1596 + 2.861/15802 + 23502 (B) 1596 +2.861, 15.302 23502 (C) 1596 +2.576,15802 + 23502 (D) 1596 + 2.576 ( 15802 + 23502) (E) 1596 + 2.576 ( 15892 23502) A hospital claims that the proportion, , of full-term babies born in their hospital that weigh more than pounds is . In a random sample of babies born in this hospital, weighed over pounds. Is there enough evidence to reject the hospital's claim at the Find the sum of the first 44 terms of the following series, to the nearest integer. 10, 14,18,... Elaborate on two instances at the workplace where "silence is golden " may be applicable. Which of the following rocks would probably be made up of the largest mineral grains? (granite, scoria, pumice, basalt) Public schools' revenue comes mainly fromlocal and federal funding.state and local funding.federal and state funding.state funding.ANSWER IS IN THE PIC i rlly need help with this gr 11 math problem