The consumption of asparagus results in the release of methanethiol and S-methyl thioesters metabolites in the urine. To some people, these metabolites have a very distinctive odor, but others cannot detect the odor ("asparagus anosmia"). How common is asparagus anosmia?
In a genetic study aiming to find the genetic markers supporting the phenotype, researchers contacted 6909 participants in a large scientific cohort and found that 4161 had asparagus anosmia. Assuming that the cohort is representative of the American adult population, obtain a 90% confidence interval for the true population of Americans with asparagus anosmia. Use technology, for instance, the 1-PropZInt function in the TI graphing calculator or the Statistics / Proportion / 1-sample function (Confidence Interval tab) on CrunchIt!.

Answers

Answer 1

Answer:

The 90% confidence interval for the true population of Americans with asparagus anosmia is (0.5926, 0.6120).

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].

Researchers contacted 6909 participants in a large scientific cohort and found that 4161 had asparagus anosmia.

This means that [tex]n = 6909, \pi = \frac{4161}{6909} = 0.6023[/tex]

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 lower limit of this interval is:

[tex]\pi - z\sqrt{\frac{\pi(1-\pi)}{n}} = 0.6023 - 1.645\sqrt{\frac{0.6023*0.3977}{6906}} = 0.5926[/tex]

The upper limit of this interval is:

[tex]\pi + z\sqrt{\frac{\pi(1-\pi)}{n}} = 0.6023 + 1.645\sqrt{\frac{0.6023*0.3977}{6906}} = 0.6120[/tex]

The 90% confidence interval for the true population of Americans with asparagus anosmia is (0.5926, 0.6120).


Related Questions

Write seven and three fifths as an improper fraction

Answers

Answer:

7.6

Step-by-step explanation:

I used a calculator

Answer:

38/5

Step-by-step explanation:

Convert the mixed number 7 3/5 Into an improper fraction first by multiplying the denominator (5) by the whole number part (7) and add the numerator (3) to get the new numerator. Place the new numerator (38) over the old denominator (5) .

According to survey​ data, the distribution of arm spans for males is approximately Normal with a mean of 71.4 inches and a standard deviation of 3.1 inches. a. What percentage of men have arm spans between 66 and 76 ​inches? b. A particular professional basketball player has an arm span of almost 89 inches. Find the​ z-score for this​ person's arm span. What percentage of males have an arm span at least as long as this​ person?

Answers

Answer:

a) 89.97% of men have arm spans between 66 and 76 ​inches.

b) The z-score for this​ person's arm span is 5.68. 0% of males have an arm span at least as long as this​ person

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.

Mean of 71.4 inches and a standard deviation of 3.1 inches.

This means that [tex]\mu = 71.4, \sigma = 3.1[/tex]

a. What percentage of men have arm spans between 66 and 76 ​inches?

The proportion is the pvalue of Z when X = 76 subtracted by the pvalue of Z  when X = 66. The percentage is the proportion multiplied by 100.

X = 76

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

[tex]Z = \frac{76 - 71.4}{3.1}[/tex]

[tex]Z = 1.48[/tex]

[tex]Z = 1.48[/tex] has a pvalue of 0.9306

X = 66

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

[tex]Z = \frac{66 - 71.4}{3.1}[/tex]

[tex]Z = -1.74[/tex]

[tex]Z = -1.74[/tex] has a pvalue of 0.0409

0.9306 - 0.0409 = 0.8997

0.8997*100% = 89.97%

89.97% of men have arm spans between 66 and 76 ​inches.

b. A particular professional basketball player has an arm span of almost 89 inches. Find the​ z-score for this​ person's arm span. What percentage of males have an arm span at least as long as this​ person?

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

[tex]Z = \frac{89 - 71.4}{3.1}[/tex]

[tex]Z = 5.68[/tex]

The z-score for this​ person's arm span is 5.68.

Z = 5.68 has a pvalue of 1

1 - 1 = 0

0% of males have an arm span at least as long as this​ person

The percentage of men who have arm spans between 66 and 76 inches is 89.97% and the percentage of males who have an arm span at least as long as this​ person is 0%.

Given :

According to survey​ data, the distribution of arm spans for males is approximately Normal with a mean of 71.4 inches and a standard deviation of 3.1 inches.

a) The formula of z-score is given below:

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

where [tex]\mu[/tex] is the mean and [tex]\sigma[/tex] is the standard deviation.

When X = 66 the formula of z-score becomes:

[tex]\rm Z = \dfrac{66-71.4}{3.1}[/tex]

Z = -1.74

The p-value regarding the (Z = -1.74) is 0.0409.

When X = 76 the formula of z-score becomes:

[tex]\rm Z = \dfrac{76-71.4}{3.1}[/tex]

Z = 1.48

The p-value regarding the (Z = 1.48) is 0.9306.

Now, the percentage of men who have arm spans between 66 and 76 inches is:

= (0.9306 - 0.0409) [tex]\times[/tex] 100 %

= 89.97%

b) Now, at X = 89 the formula of z-score becomes:

[tex]\rm Z = \dfrac{89-71.4}{3.1}[/tex]

Z = 5.68

The p-value regarding the (Z = 5.68) is 1.

So, the percentage of males who have an arm span at least as long as 89 inches ​is:

= (1 - 1) [tex]\times[/tex] 100 %

= 0%

For more information, refer to the link given below:

https://brainly.com/question/13299273

Hi!

I am here with a handful of geometry questions today. Please answer the question based off the image(s) below.

If you are not sure of the answer please leave a comment, DO NOT ANSWER THE QUESTION UNLESS YOU KNOW THE ANSWER. Please don't take me points! Thanks for understanding.

Anyways, please show all of your work and explain your thinking! Make sure to do both of them! Thanks!

Answers

9514 1404 393

Answer:

  1. area DEF = 2π cm²

  2. arc JK = 2π cm

Step-by-step explanation:

1. The area is given by ...

  A = 1/2r²θ . . . . . where r is the radius and θ is the central angle in radians

Your sector has an area of ...

  A = (1/2)(3 cm)²(80(π/180)) = (1/2)(9 cm²)(4/9π)

  A = 2π cm²

__

2. The length of an arc is ...

  s = rθ . . . . . . . where r is the radius and θ is the central angle in radians

  s = (5 cm)(72(π/180)) = (5 cm)(2/5π)

  s = 2π cm . . . arc length

_____

Additional comment

There are π radians in 180°, so an angle in degrees can be converted to an angle in radians by multiplying by π/180°. (The units of degrees cancel, leaving a pure number. "Radians" have no units.)

I don't understand this, please help ​

Answers

Answer:

∠2 = 150°, it is a supplementary angle to 30°

∠3 = 30°, it is an alternate angle to 30°

∠4 = 150°, it is a supplementary angle to 30°

∠5 = 30°, it is an alternate angle to 30°

∠6 = 150°, it is a supplementary angle to 30°

∠7 = 30°, it is an alternate angle to 30°

∠8 = 150°, it is a supplementary angle to 30°

Express each decimal to fraction 0.8255555…

Answers

Answer:

08255555/10000000 this is the answer

Answer:

0.8255555 = [tex]\frac{33}{40}[/tex]

Step-by-step explanation:

Showing the work

Rewrite the decimal number as a fraction with 1 in the denominator

0.825 = [tex]\frac{0.825}{1}[/tex]

Multiply to remove 3 decimal places. Here, you multiply top and bottom by 103 = 1000

[tex]\frac{0.825}{1}[/tex] × [tex]\frac{1000}{1000}[/tex] = [tex]\frac{825}{1000}[/tex]

Find the Greatest Common Factor (GCF) of 825 and 1000, if it exists, and reduce the fraction by dividing both numerator and denominator by GCF = 25,

[tex]\frac{825/25}{1000/25}[/tex] = [tex]\frac{33}{40}[/tex]

Therefore

X= [tex]\frac{33}{40}[/tex]

In conclusion,

0.825555 = [tex]\frac{33}{40}[/tex]

Hope it helps

Please mark me as the brainliest

Thank you

Please guys help me please no links

Answers

Answer:

it's F.

Step-by-step explanation:

i used my calculator. just trust me

The answer is F

I recommend using a scientific calculator for these types of problems if you don’t already.

Joseph's lunch at a restaurant costs $13.00, without tax. He leaves the waiter a tip of 17%
of the cost of the lunch, without tax. What is the total cost of the lunch, including the tip,
without tax?
A
$2.21
$10.79
C
$13.17
D
$15.21

Answers

change 17% to a decimal
0.17 x 13= 2.21
add 2.21 to 13 , which is 15.21

state three (3) uses of graphs


Answers

1. Graphs can help you figure out the slope of a line faster. 2. Graphs can help you compare two or more lines. 3. Graphs can help you determine the y-intercept by just looking at the graph.

At the start of the day, Celia has a checking account balance of $423.75. She used her debit card to make a purchase of $42.30 for groceries and
$15.00 for gas. She also withdrew money from an ATM for $40.00. How much money is now in Grace's checking account?
WRITE WITH A S, COMMA AND CENTS EXAMPLE 3456.456 IS $3,456.46 AND 45 IS $45.00

Answers

The answer is $326.45

Answer this for 10 points

Answers

Answer:

D) -2

Step-by-step explanation:

Slope = -3

(1, -9)

y - y1 = m(x - x1)

y + 9 = -3(x - 1)

y + 9 = -3x + 3

y = -3x - 6

y = -3x - 6

0 = -3x - 6

6 = -3x

x = -2

divide 270 in the ratio 3:2:1​

Answers

3 + 2 + 1 = 6

270 ÷ 6 = 45

45 × 3 = 135

45 × 2 = 90

45 × 1 = 45

3 : 2 : 1

135 : 90 : 45

The question that is asked...

Answers

The answer is A. 90+13+x= 180
As all the angles on a straight line amount to 180°

man drove his car a distance of 315 miles in 5 hours. If continuing at this rate is possible, he will travel ____ miles in 9 hours.

Answers

Answer:

567

Step-by-step explanation:

Please mark brainliest

Answer:

567

Step-by-step explanation:

OMG PLEASE HELP PLEASE OMG HELP ME HELP PLZ!!!!!!!!!! HELPPPPPPPPPPPPp

Answers

17.5 mark brainlist plssssssssssssss

Challenge A bag contains pennies, nickels, dimes, and quarters. There are 50 coins in all. Of the
coins, 10% are pennies and 38% are dimes. There are 2 more nickels than pennies. How much
money does the bag contain?

Answers

Answer:

5 pennies

7 nickels

19 dimes

$2.3

Step-by-step explanation:

first i like to find 1%

50/100=1%

50/100=0.5

then multiply to find %'s

0.5x10=pennies

0.5x10=5

0.5x38=dimes

0.5x38=19

since there are 2 more nickels than pennies there are 7 nickels since there are 5 pennies

then find each value and add

5x.01+7x.05+19x.10

0.05+0.35+1.9=$2.3

Condense the log equation: 4 log x + log y - 5 log z

Answers

Answer:

The condensed log equation is: [tex]\log{\frac{x^4y}{z^5}}[/tex]

Step-by-step explanation:

We use these following logarithm properties to solve this question:

[tex]a\log{x} = \log{x^a}[/tex]

[tex]\log{a} + \log{b} = \log{ab}[/tex]

[tex]\log{a} - \log{b} = \log{\frac{a}{b}}[/tex]

In this question:

[tex]4\log{x} = \log{x^4}[/tex]

[tex]5\log{5} = \log{z^5}[/tex]

So

[tex]4\log{x} + \log{y} - 5\log{z}[/tex]

Becomes:

[tex]\log{x^4} + \log{y} - \log{z^5}[/tex]

Now applying the addition and subtraction properties, we have:

[tex]\log{\frac{x^4y}{z^5}}[/tex]

The condensed log equation is: [tex]\log{\frac{x^4y}{z^5}}[/tex]

Which number is equal to 6^3?

A. 18
B. 36
C. 216
D. 666

Answers

Answer:

C. 216

Step-by-step explanation:

6³ = 6 x 6 x 6

6 x 6 = 36

36 x 6 = 180 + 36

180 + 36 = 216

hope this helps

C. 216
6•6=36
36•6=216

please someone helpme

Answers

Answer:

[tex]\displaystyle t = \frac{2 \pi}{3}, \ \frac{4 \pi}{3}[/tex]

General Formulas and Concepts:

Pre-Algebra

Order of Operations: BPEMDAS

Brackets Parenthesis Exponents Multiplication Division Addition Subtraction Left to Right  

Equality Properties

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

Algebra I

FunctionsFunction Notation[Interval Notation] - [Brackets] imply inclusive, (Parenthesis) imply exclusive

Pre-Calculus

Unit Circle

Calculus

Derivatives

Derivative Notation

The definition of a derivative is the slope of the tangent line

Basic Power Rule:

f(x) = cxⁿ f’(x) = c·nxⁿ⁻¹

Derivative Property [Addition/Subtraction]:                                                          [tex]\displaystyle \frac{d}{dx}[f(x) + g(x)] = \frac{d}{dx}[f(x)] + \frac{d}{dx}[g(x)][/tex]

Derivative Property [Multiplied Constant]:                                                            [tex]\displaystyle \frac{d}{dx} [cf(x)] = c \cdot f'(x)[/tex]

Trig Derivative:                                                                                                        [tex]\displaystyle \frac{d}{dx}[sinu] = u'cosu[/tex]

Step-by-step explanation:

Step 1: Define

[Given] q(t) = t + 2sint

[Given] Interval [0, 2π]

[Solve] q'(t) = 0

Horizontal tangent line have a slope of 0

Step 2: Differentiate

[Derivative] Basic Power Rule/Trig Derivative [Derivative Prop - Add]:      [tex]\displaystyle q'(t) = 1 \cdot t^{1 - 1} + 1 \cdot 2cost[/tex][Derivative] Simplify exponent:                                                                     [tex]\displaystyle q'(t) = 1 \cdot t^{0} + 1 \cdot 2cost[/tex][Derivative] Evaluate exponent:                                                                    [tex]\displaystyle q'(t) = 1 \cdot 1 + 1 \cdot 2cost[/tex][Derivative] Multiply:                                                                                       [tex]\displaystyle q'(t) = 1 + 2cost[/tex]

Step 3: Solve

[Derivative] Substitute in function value:                                                      [tex]\displaystyle 0 = 1 + 2cost[/tex][Subtraction Property of Equality] Isolate t term:                                          [tex]\displaystyle -1 = 2cost[/tex]Rewrite:                                                                                                           [tex]\displaystyle 2cost = -1[/tex][Division Property of Equality] Isolate trig t term:                                         [tex]\displaystyle cost = \frac{-1}{2}[/tex][Equality Property] Inverse Trig:                                                                    [tex]\displaystyle t = cos^{-1}(\frac{-1}{2})[/tex]Evaluate [Unit Circle, Interval]:                                                                       [tex]\displaystyle t = \frac{2 \pi}{3}, \ \frac{4 \pi}{3}[/tex]

Topic: AP Calculus AB/BC (Calculus I/II)

Unit: Derivatives

Book: College Calculus 10e

Do you guys now the answer I need it ASAP please

Answers

Answer:I think that it would be either b or c

Step-by-step explanation:

I think it’s B!!!!!!

Please answer ASAP this is due tomorrow

Answers

Answer:

227.08in^2

You want to find the surface area for this problem. SA=2lw+2lh+2hw

Step-by-step explanation:

L=2.5

W=7.4

H=9.6

SA=2lw+2lh+2hw

SA=2(2.5x7.4)+2(2.5x9.6)+2(9.6x7.4)

SA=37+142.08+48

SA=227.08in^2

need help please make sure your right people have been saying wrong answers​

Answers

Answer:

C

Step-by-step explanation:

Trust me, take the square root of 24, which divides into 2 x 2 x 2 x 3, and you pull a pair of 2 out, left inside a 6

Answer:

Step-by-step explanation:

How many and what type of solution(s) does the equation have?8p^2=24p−10

Answers

Answer:

2 real solutions

Step-by-step explanation:

to understand thisyou need to know about:discriminantPEMDAStips and formulas[tex]D=b^{2}-4ac[/tex]D>0 (2 real solutions)D=0 (1 real solution)D<0 (2 imaginary solutions) or (no real solutions)let's solve:move left hand side expressions to right hand side and change its sign:8p²-24p+10=0divide both sides by 2 :4p²-12p+5=0

the quadratic equation standard form is

ax²+bx+c=0

therefore we get

a=4b=-12c=5

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

substitute the value of a,b and c into the discriminant: D=-12²-4.4.5simplify square:144-4.4.5simplify multiplication:144-80simplify substraction:64

since we got D>0

therefore

the quadratic equation has 2 real solutions

The proportion of California residents who reported insufficient rest or sleep during each of the preceding 30 days is 8.0%, while this proportion is 8.8% for Oregon residents. These data are based on simple random samples of 11,545 California and 4,691 Oregon residents.
(a) Conduct a hypothesis test to determine if these data provide strong evidence the rate of sleep deprivation is different for the two states.
(b) It is possible the conclusion of the test in part (a) is incorrect. If this is the case, what type of error was made?

Answers

Step-by-step explanation:

We start by stating the null hypothesis

H0: p1 = p2

No difference is existent

H1: p2 not equal to p2

There is a difference

We find the z statistic using microsoft excel or using the formula in the attachment

= -1.68

From the normal table, p value = 0.099

The p value is greater than 0.05 so we fail to reject the null hypothesis and conclude there is no difference

B. If answer in part a is incorrect then we have made a type ii error. A type 2 error occurs when we accept a false null hypothesis.

mareli rides her dirt bike at 20 meters/second for 500 seconds, how far did she ride?​

Answers

Answer:

25 meters

Step-by-step explanation:

500/20 =  25

25 meters

Hope that helps!

Answer:

10,000 meters

Step-by-step explanation:

20*500=10,000

Which expression is equivalent to (2) -3 (4) ô?

Answers

Answer:

if any number power of 0 is 1

so, (4)^0 =1

if any number power of -1 is equal to one divide this number.

like;

a^(-1) = 1/a

Therefore,

2^(-3) = 2^(-1) x  2^(-1) x  2^(-1)

         = 1/2 x   1/2 x   1/2

Hence solution of 2^(-3). (4) ^0 is,

1/2 x   1/2 x   1/2 x 1

                             

Step-by-step explanation:

SOMEONE PLEASE ANSWER AND EXPLAIN I’LL MARK BRAINLIEST THANK YOU

Answers

Answer:

20 visits.

Step-by-step explanation:

Fitness Universe has a 1 time payment of $50, and each visit will cost $5.50

Non-members pay $8 per visit. Let each visit be signified by the variable, v. Set the equation:

5.50v + 50 = 8v

Isolate the variable, v. Note the equal sign, what you do to one side, you do to the other. Subtract 5.50v from both sides:

5.50v (-5.50v) + 50 = 8v (-5.50v)

50 = 8v - 5.50v

50 = 2.50v

Isolate the variable, v. Divide 2.50 from both sides:

(50)/2.50 = (2.50v)/2.50

v = 50/2.50

v = 20

Stuart must visit 20 times to break even, in which it will become cheaper after the 20th visit.

Solve for x. Round your answer to the nearest tenth. Remember, if your solving for the angle x, you must use the inverse function

Answers

Answer:

x ≈ 21.36

Step-by-step explanation:

sin31 = 11/x

xsin31 = 11

x = 11/sin31 ≈ 21.36

Can anyone help me on this please

Answers

Answer:

y = x - 8

Step-by-step explanation:

y = mx + b

M is your slope, 1. 1x can be rewritten as x.

Your Y intercept is B, therefore -8.

y = x - 8. When you plug in the numbers.

9) Find the unit rate:
40 cookies for $3.25

Answers

The answer is 130 dollars

The tip of a 8 cm minute hand of a clock sweeps out circular arcs.

What is the length of the arc made by the tip of the minute hand between 3:12 and 3:32?

Use 3.14 for pi. Round your answer to the nearest hundredth.

Enter your answer in the box.

Answers

Answer:

16.75

Step-by-step explanation:

20/60=x/360

x=120 degree angle

120/360=x/2pi8

1/3=x/16pi

16pi/3=x

x=16.75 arc length

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I need help asapWhat is a homopolar motor? a. The first electric motor ever made. b. A motor made by in the North Pole. c. A motor used in homes in the winter. Why is the heart so heard to cut through? I need help! anyone trynna help? can some one helpSigmund Freud was a psychologist that developed a number of new ideas about how our minds work. The art movement that Freud most heavily influenced was Surrealism which was inspired by Freuds idea that dreams could reveal hidden ideas.key words: advocate, equal, employment, end, segregation, armed, forces, actions, civil, rights, movement factor the following quadratic equation 4x^2-8x+3 The following is a student draft. It may contain errors.Community Gardens (1) Community gardens, with their rows of bountiful produce, are becoming popular across the United States and the world because they provide places where people get to work with their hands, where people find a peaceful, quiet place, and where communities can come together. (2) More people are keen on reaping the benefits of these gardens, which include improved overall health, better community relationships, and a healthier environment. (3) Starting a community garden is a detailed process. (4) Like with any group project, a community garden requires like-minded individuals to come together. (5) So, the first step is to create a planning group. (6) The planning group should include people committed and willing to make time for the community garden. (7) Next, it's important to find a location for the garden. (8) Some local governments set aside lots for people to use as community gardens. (9) Some organizations help people rent or purchase spaces for gardening. (10) Once the location is chosen, the final step is to decide the layout or structure of the garden. (11) For example, some gardens use wooden crates to plant vegetables or fruits. (12) Other gardens arrange plants in rows in small plots in the ground. (13) Based on the layout, people can begin planting in the garden. (14) Community gardens require teamwork and dedication, which can help bring a community closer. Five people will equally share two pizzas. How much pizza will each person recieve. EASY EXTRA POINTS ASAP Write a ORIGINAL poem on nature/climate change Mikala pours a tablespoon of salt into a beaker of water. Diffusion will cause the salt molecules to dissolve in the molecules of water. How could Mikala increase the diffusion rate of the salt molecules? A. Mikala could remove all sources of light from the beaker. B. Mikala could slowly pour more water into the beaker.C. Mikala could decrease the temperature of the solution. D. Mikala could increase the temperature of the solution. What is the theme of the poem, Two Moods from the Hill.A) Childhood is often cut short by lifes worries.B) Nature is reflected in the beauty of the cycle of life.C) With age comes reflection on the choices one has made.D) Rest and relaxation are an important part of life. Dilate Point B by a scale factor of 1/2 Which of the following laws made it illegal for enslaved Black people to learn to read and write?A.Fugitive Slave ActB.Negro Act of 1740C.Compromise of 1877D.Three-Fifths Compromise help me please and thank you Fix the following sentence by replacing the incorrect transition wordwith a correct one. Ms. Mach believes chocolate chip ice cream to be the best ice cream; additionally, Ms. Herda finds coconut icecream to be the best significant is to trivial as MISERABLE is to ______. *Buoyant Whimsical RaspyNatured Please help me friends?? Help me with this!! Will mark Brainliest The markets in the urban area that have many shops, are popularly called _________. Jane goes to H&M for some Fall clothes. She finds a scarf for $24.99, a shirt for $35.50, and a pair of jeans for $67.85. If H&M was having a Fall Day sale where everything was 35% off, how much did Jane spend at H&M? Joe and three friends went to Texas Roadhouse for dinner the total bill was $76.25 they left server a 20% tip how much was the tip what was the total bill how much should each person pay