don't know if my answer is right

Answer:

A sample size of 657 is needed.

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].

The margin of error is:

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

95% confidence level

So [tex]\alpha = 0.05[/tex], z is the value of Z that has a pvalue of [tex]1 - \frac{0.05}{2} = 0.975[/tex], so [tex]Z = 1.96[/tex].

In the past, 19% of all homes with a stay-at-home parent had the father as the stay-at-home parent.

This means that [tex]\pi = 0.19[/tex]

(a) What sample size is needed if the research firm's goal is to estimate the current proportion of homes with a stay-at-home parent in which the father is the stay-at-home parent with a margin of error of 0.03?

A sample size of n is needed.

n is found when [tex]M = 0.03[/tex]

Then

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

[tex]0.03 = 1.96\sqrt{\frac{0.19*0.81}{n}}[/tex]

[tex]0.03\sqrt{n} = 1.96\sqrt{0.19*0.81}[/tex]

[tex]\sqrt{n} = \frac{1.96\sqrt{0.19*0.81}}{0.03}[/tex]

[tex](\sqrt{n})^{2} = (\frac{1.96\sqrt{0.19*0.81}}{0.03})^{2}[/tex]

[tex]n = 656.91[/tex]

Rounding up to the nearest whole number.

A sample size of 657 is needed.

Answer:

The p-value of the test is 0.023.

Step-by-step explanation:

In this case we need to determine whether the addition of several advertising campaigns increased the sales or not.

The hypothesis can be defined as follows:

H₀: The stores average sales is $8000 per day, i.e. μ = 8000.

Hₐ: The stores average sales is more than $8000 per day, i.e. μ > 8000.

The information provided is:

 [tex]n=64\\\bar x=\$8300\\\sigma=\$1200[/tex]

As the population standard deviation is provided, we will use a z-test for single mean.

Compute the test statistic value as follows:

 [tex]z=\frac{\bar x-\mu}{\sigma/\sqrt{n}}=\frac{8300-8000}{1200/\sqrt{64}}=2[/tex]

The test statistic value is 2.

Decision rule:

If the p-value of the test is less than the significance level then the null hypothesis will be rejected.

Compute the p-value for the two-tailed test as follows:

 [tex]p-value=P(Z>2)\\=1-P(Z<2)\\=1-0.97725\\=0.02275\\\approx 0.023[/tex]

*Use a z-table for the probability.

The p-value of the test is 0.023.

Answer:

Answers are below

Step-by-step explanation:

Percent means "out of 100" so 35% is 35/100. We can simplify this fraction by dividing the numerator and denominator by 5. 35/100 / 5 = 7/20.

7/20 multiply the numerator and denominator by 5.

7/20 x 5 = 35/100

If this answer is correct, please make me Brainliest!

Answer:

b and c

Step-by-step explanation:

Answer:

93.25% probability that they have taken this steroid

Step-by-step explanation:

Bayes Theorem:

Two events, A and B.

[tex]P(B|A) = \frac{P(B)*P(A|B)}{P(A)}[/tex]

In which P(B|A) is the probability of B happening when A has happened and P(A|B) is the probability of A happening when B has happened.

In this question:

Event A: Positive test

Event B: Taking the steroid.

Suppose the probability of an athlete taking a certain illegal steroid is 10%.

This means that [tex]P(B) = 0.1[/tex]

Given that the athlete has taken this steroid, the probability of a positive test result is 0.995.

This means that [tex]P(A|B) = 0.995[/tex]

Positive test:

99.5% of 10%(If the athlete has taken).

100-99.2 = 0.8% of 100-10 = 90%(Athlete has not taken)

Then

[tex]P(B) = 0.995*0.1 + 0.008*0.9 = 0.1067[/tex]

Given that a positive test result has been observed for an athlete, what is the probability that they have taken this steroid

[tex]P(B|A) = \frac{P(B)*P(A|B)}{P(A)} = \frac{0.1*0.995}{0.1067} = 0.9325[/tex]

93.25% probability that they have taken this steroid

Answer:

3.74% probability that her baby has T18

Step-by-step explanation:

Bayes Theorem:

Two events, A and B.

[tex]P(B|A) = \frac{P(B)*P(A|B)}{P(A)}[/tex]

In which P(B|A) is the probability of B happening when A has happened and P(A|B) is the probability of A happening when B has happened.

In this question:

Event A: Positive test.

Event B: The baby having T18.

T18 occurs in only 1 in 2500 pregnancies in the U.S.

This means that [tex]P(B) = \frac{1}{2500} = 0.0004[/tex]

The probability of a positive test result for a baby with T18 is 0.97.

This means that [tex]P(A|B) = 0.97[/tex]

The overall probability of a positive test result is 0.010384.

This means that [tex]P(A) = 0.010384[/tex]

What is the probability that her baby has T18

[tex]P(B|A) = \frac{0.0004*0.97}{0.010384} = 0.0374[/tex]

3.74% probability that her baby has T18

Answer:

The equation for the height of the penny in function of time is:

[tex]h(t)=1451-16t^2[/tex]

After 7 seconds, the penny will be at a height of 667 feet.

Step-by-step explanation:

The penny will have a free fall.

The initial velocity is zero, and the initial height is h(0)=1,451.

The acceleration will be the gravity, that has a value g=32 ft/s^2.

Then, we can model this starting by the speed:

[tex]dv/dt=-g\\\\v(t)=v_0-gt=-gt[/tex]

Then, the height becomes:

[tex]dh/dt=v(t)=-gt\\\\h(t)=h_0-\dfrac{gt^2}{2}=1451-\dfrac{32}{2}t^2\\\\\\h(t)=1451-16t^2[/tex]

The approximate height of the penny after 7 seconds can be calculated as:

[tex]h(7)=1451-16(7^2)=1451-16*49=1451-784=667[/tex]

After 7 seconds, the penny will be at a height of 667 feet.

Answer:

5/30

Step-by-step explanation:

5/30 = 1/6 =0.166666666...

The fraction equals a repeating decimal is 5/30.

A decimal numeral system is the standard system for denoting integer and non-integer numbers. The way of denoting numbers in the decimal system is often referred to as decimal notation.

Now the given fractions are,

30/50

13/25

5/30

13/10

Converting them into decimals we get,

30/50 = 0.6

13/25 = 0.52

5/30 = 0.1666..

13/10 = 1.3

Thus the repeating decimal is 0.1666..

So, the fraction with repeating decimal is 5/30 = 0.1666..

Thus, the fraction equals a repeating decimal is 5/30.

To learn more about fraction :

brainly.com/question/1301963

#SPJ2

Answer:

351.86

Step-by-step explanation:

Answer:

Step-by-step explanation:

Since each tank is cylindrical, we would apply the formula for determining the total surface area of a cylinder which is expressed as

Total surface area = 2πr² + 2πrh

Where

r represents the height of the cylinder.

h represents the height of the cylinder.

π = 3.14

From the information given,

Height = 1.9

Diameter = 1.4

Radius = diameter/2 = 1.4/2 = 0.7

Total surface area = 2 × 3.14 × 0.7² + 2 × 3.14 × 0.7 × 1.9 = 3.0772 + 8.3524 = 11.4296 m²

Total surface area of the 3 cylinders = 11.4296 × 3 = 34.29 m²

Since a tin of paint covers 5 m², the number of tins paints that Tim will need to buy is

34.29/5 = 6.858

Since the tins of paint must be whole numbers, he needs to buy 7 tins of paints.

Answer:

0.072

Step-by-step explanation:

Answer:0.072

Step-by-step explanation:

7.2% = 7.2/100

7.2 ➗ 100=0.072

Answer:

No one knows. Jk just go look at the other brainly links. the question has already been asked and answered so you can go see them there.

Step-by-step explanation:

:)

Answer:

There are 11 parts of fruit: 4-strawberry, 3- grape, 2, cherry, 1- apple, 1-orange 4/11 from the entine quantity of fruits- strawberry

3/11-grapes

2/11- cherries

1/11- apples

1/11- oranges } ⇒ the quantity of oranges and apples are equal Hope it helps ;>

Answer:

[tex]x=30\\y=68\\z=82[/tex]

Step-by-step explanation:

x = measure of the first angle

y = measure of the second angle

z = measure of the third angle

The sum of the measures of the second and third (y+z) is five times the measure of the first angle (=5x)

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

The third angle is 14 more than the second

[tex]z=y+14[/tex]

And remember that the sum of these three angles must be equal to 180.

[tex]x+y+z=180[/tex]

Let's take these equations

[tex]y+z=5x\\z=y+14\\x+y+z=180[/tex]

If you take a look at the first equation, we have y+z = 5x and we have y+z in the third equation as well, we can replace that....

[tex]x+y+z=180\\x+(y+z)=180\\x+(5x)=180[/tex]

Distribute the + sign

[tex]x+5x=180[/tex]

Combine like terms;

[tex]6x=180[/tex]

Divide by 6.

[tex]x=\frac{180}{6}\\ x=30[/tex]

We have now defined that the measure of the first angle is 30º.

Let's take another equation... for example [tex]z=y+14[/tex]

I'm going to take this one because if I replace x and z in the third equation, all I'll have left will be y.

[tex]x+y+z=180\\30+y+(y+14)=180[/tex]

Distribute the + sign and Combine like terms;

[tex]30+y+y+14=180\\44+2y=180\\[/tex]

Subtract 44 to isolate 2y.

[tex]2y=180-44\\2y=136[/tex]

Now divide by 2.

[tex]y=\frac{136}{2}\\ y=68[/tex]

We already have the value of x and y. Once again, replacing this in the third equation will leave us with z to solve for.

[tex]x+y+z=180\\30+68+z=180\\98+z=180\\z=180-98\\z=82[/tex]

Answer:

a) so the correct answer is that the probability that method A has been taught is 0.4737

b) the probability that B receives A is 0.5

Step-by-step explanation:

With the previous data we know that 3 methods teach an industrial skill and when putting into practice a worker does not learn, we have the failure rates like this:

method A fails 15%

method B fails: 5%

method C fails: 10%

usage percentages:

A: 30%

B: 40%

C: 30%

a) the probability that method A has been taught is as follows:

P (failure rate) = P (A) * P (failure rate A) + P (B) * P (failure rate B) + P (C) * P (failure rate C)

we replace the data obtaining:

P = 0.3 * 0.15 + 0.4 * 0.05 + 0.3 * 0.1 = 0.095

P ( failure rate A) = P (A) * P (failure rate A) / P (failure rate)

we replace the data obtaining:

 0.3 * 0.15 / 0.095 = 0.4737

so the correct answer is that the probability that method A has been taught is 0.4737

b) the probability that B receives A is as follows:

P (B | A) = P (B) = 0.50

Answer:

Step-by-step explanation:

The question is incomplete. The complete question is

The management of Discount Furniture, a chain of discount furniture stores in the Northeast, designed an incentive plan for salespeople. To evaluate this innovative plan, 12 salespeople were selected at random, and their weekly incomes before and after the plan were recorded.

Salesperson Before After

Sid Mahone $320 $340

Carol Quick 290 285

Tom Jackson 421 475

Andy Jones 510 510

Jean Sloan 210 210

Jack Walker 402 500

Peg Mancuso 625 631

Anita Loma 560 560

John Cuso 360 365

Carl Utz 431 431

A. S. Kushner 506 525

Fern Lawton 505 619

Solution:

Corresponding income of salespersons before and after form matched pairs.

The data for the test are the differences between the income is salespersons.

μd = the​ income before minus their income after.

Bedore after diff

320 340 -20

290 285 5

421 475 - 54

510 510 0

210 210 0

402 500 - 98

625 631 -6

569 560 0

360 365 - 5

431 431 0

506 525 - 19

505 619 - 114

Sample mean, xd

= (- 20 + 5 - 54 + 0 + 0 - 98 - 6 + 0 - 5 + 0 + - 19 - 114)/12 = - 25.92

xd = - 25.92

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

n = 12

Summation(x - mean)² = (- 20 + 25.92)^2 + (5 - 25.92)^2 + (- 54 + 25.92)^2+ (0 + 25.92)^2 + (0 + 25.92)^2 + ( - 98 + 25.92)^2 + ( - 6 + 25.92)^2 + (0 + 25.92)^2 + (- 5 + 25.92)^2 + (0 + 25.92)^2 + (- 19 + 25.92)^2 + (- 114 + 25.92)^2 = 17784.5168

Standard deviation = √(17784.5168/12

sd = 38.5

For the null hypothesis

H0: μd ≥ 0

For the alternative hypothesis

H1: μd < 0

1) The distribution is a students t. Therefore, degree of freedom, df = n - 1 = 12 - 1 = 11

2) The formula for determining the test statistic is

t = (xd - μd)/(sd/√n)

t = ( - 25.92- 0)/(38.5/√12)

t = - 2.33

3) We would determine the probability value by using the t test calculator.

p = 0.02

4) Assume alpha = 0.05

Since alpha, 0.05 > than the p value, 0.02, then we would reject the null hypothesis. We can conclude that at 5% significance level, there is a significant increase in the typical salesperson’s weekly income due to the innovative incentive plan

Answer:

on what

Step-by-step explanation: normaly you have a button that you can have certain characters

Answer:

Do my question i will do yours

Step-by-step explanation:

Answer:

The Answer is C

Step-by-step explanation:

Answer:

8. -⅓ cos³x + C

9. sec x + eˣ + C

Step-by-step explanation:

8. ∫ sin x cos²x dx

If u = cos x, then du = -sin x dx.

∫ -u² du

-⅓ u³ + C

-⅓ cos³x + C

9. ∫ (sec x tan x + eˣ) dx

∫ sec x tan x dx + ∫ eˣ dx

These are both standard integrals:

sec x + eˣ + C

Question 8:

∫sinxcos²xdx

∫-u²du (let u = cos(x))

-∫u²du

-u(^2+1)/2+1

-cos^(2+1)(x)/2+1

-1/3cos³(x)

-1/3cos³(x) + C

Question 9:

∫(secxtanx + eˣ)dx

∫sec(x)tan(x)dx + ∫eˣdx (apply sum rule)

sec(x) + eˣ (sec(x)tan(x)dx = sec(x) and eˣdx = eˣ)

sec(x) + eˣ + C

Best of Luck!

Answer:

the x intercept is 2

Step-by-step explanation:

I just went over this unit

Answer:

2

Step-by-step explanation:

Answer:

i think its 248m^2

Step-by-step explanation:

Answer:

16

Step-by-step explanation:

distance between point x and z is 8 units

distance between point z and y is 4 units

8 * 4 = 32

formula for area of a triangle (l * w)/2

plugin: (8 * 4)/2 = 16

Answer:

$190.08

Step-by-step explanation:

Take 27% of the total $704 spent in July:

0.27($704) = $190.08

He spent an estimated $190.08 on clothing in July.

Answer:

Step-by-step explanation:

I THINK 140

Answer:2c^2

Step-by-step explanation:

34c^3 and 2c^5

34c^3=2 x 16 x c x c^2

2c^5=2 x c^2 x c^3

Greatest common factor =2 x c^2

Greatest common factor =2c^2

Answer: so you would do 17 plus ten which is 27 so triple 3 so your answer is 27^3

Step-by-step explanation:

sum so your adding plus you need the exponent which is times 3

Question:

1. How many full boxes of lemon bars can Shira fill?

2. How many delicious lemon bars will she be taking home?

Answer:

1. Number of filled box = 21

2. Number of take home = 2

Step-by-step explanation:

Given

Number of lemon bars = 170

Each bar contains 8 lemon bars

Required

(1) & (2)

To calculate the number of boxes Shira can fill, we simply divide the total number of bars by constituents of each bar .

i.e.

Number of filled box = 170/8

Number of filled box = 21.25

But here, we only need the quotient of the division because it represents the filled boxed.

So,

Number of filled box = 21

Calculating the number of take home.

We'll follow the same steps as (1) above but here, we only need the remainder of the division.

When 170 is divided by 8, the remainder is 2.

So, number of boxes she'll take home is 2.

See calculation below

Number of take home = 170 % 8

Number of take home = 2

Answer:

Option D: 5591.93

Step-by-step explanation:

The best way to understand this question is to apply the formula in an indirect manner;

P - Principle number, Starting Value

T - Time

I - Interest

Let us convert the interest into decimal form, such that 3.8% is shifted two decimal points to the right ⇒ 0.038. Now add 1 to this value to get ⇒ 1.038. By PEDMAS, you would first raise this value to the span of 3 years as such:

(1.038)^3 = 1.118386872.......

The final step would by to multiply the starting value (investment $) $ 5,000 by this continuing value of 1.118386872:

5,000(1.118386872) = 5591.93436 ⇒ Rounded to (About) 5591.93

Answer:D

Step-by-step explanation:

principal=p=$5000

Rate=r=3.8%

Time=n=3 years

amount=a

a=p(1+r/100)^n

a=5000(1+3.8/100)^3

a=5000(1+0.038)^3

a=5000(1.038)^3

a=5000 x 1.038 x 1.038 x 1.038

a=5591.93

a=$5591.93

Answer:150 branliest

Step-by-step explanation:

Answer:

150

Step-by-step explanation:

360/(5+7)=30

30*5=150

Answer:

0.004

Step-by-step explanation:

The probability of rolling any number is 1/6 so that times 3 is 1/216 that as a decimal i 0.004

Answer:

C.  [tex]\frac{\sqrt{5} }{8}[/tex]

Step-by-step explanation:

This expression can be rewritten as [tex]\frac{\sqrt{5} }{\sqrt{64} }[/tex].

Since the square root of 5 is prime and does not have any perfect square factors, it cannot be simplified. However, the square root of 64 is equal to 8, so our final simplified radical expression would be [tex]\frac{\sqrt{5} }{8}[/tex], which is option C.

HOPE THIS HELPED! :)

Answer:

C is the answer

Step-by-step explanation:

You have to rewrite as [tex]\sqrt{5}[/tex]/[tex]\sqrt{64}[/tex]. Then you have to simplify the denominator which is 8. That is how you get your answer.

Hope this helps.

Answer:

Denote B(x, y), we have:

-10 + x = 2 x (-16) => x = -22

  8 + y = 2 x 6 => y = 4

=> B(-22, 4)

Hope this helps!

:)