At one school, the average amount of time tenth-graders spend watching television each week is 21.6 hours. The principal introduces a campaign to encourage the students to watch less television. One year later, the principal performs a significance test using α= 0.05 to determine whether the average amount of time spent watching television per week has decreased. The hypotheses are:
H0: µ = 21.6 hours
Ha: µ < 21.6 hours

If the P-value 0.04 and a decision error is made, what type of error is it? Explain.

a) Type II error. We conclude that the average amount of time spent watching television each week is 21.6 hours when it is in fact less.
b) Type I error. We conclude that the average amount of time spent watching television each week is 21.6 hours when it is in fact less.
c) Type II error. We conclude that the average amount of time spent watching television each week is less than 21.6 hours when it is in fact not.
d) Type I error. We conclude that the average amount of time spent watching television each week is less than 21.6 hours when it is in fact not.

Answer:Correct Answer: A

Explanation: Choice A is the correct answer. Let x be the number of hours that the babysitter worked. Since the babysitter earns money at a rate of $8 per hour, she earned 8x dollars for the x hours worked. If the babysitter gets both children to bed on time, the babysitter earns an additional $3 tip. Therefore, the babysitter earned a total amount of 8x + 3 dollars.

Choice B is incorrect since the tip and the rate per hour have been interchanged in the expression. Choices C and D are incorrect since the number of children is not part of how the babysitter’s earnings are calculated.

Answer:

C

Step-by-step explanation:

[tex]x^{2}[/tex]+[tex]y^{2}[/tex]= [tex]\sqrt{x^{2}+y^{2} }[/tex]+2y

Answer:

The equation of equivalent is,[tex]x^{4}+ y^{4} +3 y^{2} +2x^{2} y^{2} -4y^{3} -4 x^{2} y-x^{2} =0[/tex]

Step-by-step explanation:

If two systems of equations have the same solution, they are equivalent (s). This article explains how to determine whether two systems are equal. Equivalent systems are sets of equations that have the same solution.

Given, r = 1+2sinФ

[tex]r^{2} =r+2rsin[/tex]θ

[tex]x^{2}+ y^{2} =r+2y\\x^{2} + y^{2} -2y=r\\[/tex]

Squaring, both side:

[tex](x^{4} +y^{4} -2 y^{2}) = r^{2} \\x^{4}+ y^{4} + 4y^{2}+2 x^{2} y^{2} - 4y^{3} -4x^{2} y =x^{2} +y^{2} \\x^{4} + y^{4} +3 y^{2} +2 x^{2} y^{2} -4y^{3} -4x^{2} y^}-x^{2} =0[/tex]

To know more about equivalent equation here, https://brainly.com/question/2972832

#SPJ2

Answer:

The old version awards 50 more points for each level

Step-by-step explanation:

Function Modeling

Two models are being compared: The old model relates the total number of points awarded in a computer game (y) with the number of levels completed (x) as

[tex]y=175x+150[/tex]

The new model is given as a graph. To find the equation of the line we must locate a couple of 'good' points. The graph is very clear, so we select the extreme points (1,250) (9,1250)

Find the equation of the line with the point-point formula

[tex]\displaystyle y-250=\frac{1250-250}{9-1}(x-1)[/tex]

[tex]\displaystyle y-250=\frac{1000}{8}(x-1)[/tex]

[tex]y=250+125x-125[/tex]

[tex]y=125x+125[/tex]

Comparing the new function with the old function we can note the coefficient of x (the slope of the line) is 50 points more in the old version than the points in the new version.

Thus the answer is

The old version awards 50 more points for each level

Answer: the answer is B

Step-by-step explanation:

Answer:

the answer is B,C,F

Step-by-step explanation:

The correct options are,
1. Add 3.4 to both sides of the equation.
2. 12.7 + 3.4 = 16.1, so j = 16.1.
3. Substitute 16.1 for j to check the solution.

The process in mathematics to operate and interpret the function to make the function or expression simple or more understandable is called simplifying and the process is called simplification.

The steps to solve the equation: 12.7 = j - 3.4 are as follows,

Add 3.4 to both sides of the equation,

12.7 + 3.4 = j

Solve for j,

16.1 = j

So the solution is j = 16.1

To check the solution, you would substitute 16.1 for j in the original equation and see if both sides are equal.

Learn more about simplification here:

https://brainly.com/question/12501526

#SPJ6

The volume of the cylinder is 401.92 cube m.

Step-by-step explanation:

Given,

A cylinder of height 2x inscribed in a sphere of radius 8 m.

The center of the sphere is the midpoint of the altitude that joins the centers of the bases of the cylinder.

To find the volume of the cylinder.

Formula

The volume of a cylinder with h as height and r as radius is = πr²h

Since,

The cylinder is inscribed in the sphere

The radius (r) of the cylinder = 4 m

The height (h) of the cylinder = 8 m

So,

The volume of the cylinder = π×4²×8 cube m

= 128π cube m [ taking π=3.14]

= 128×3.14 cube m

= 401.92 cube m

Hence,

The volume of the cylinder is 401.92 cube m.

The volume of the cylinder is 128πx.

The volume of a cylinder can be found using the formula V = πr²h, where r is the radius of the cylinder's base and h is the height of the cylinder. In this case, the cylinder is inscribed in a sphere with radius 8 meters and the center of the sphere is the midpoint of the altitude that joins the centers of the bases of the cylinder. Since the cylinder is inscribed in the sphere, the diameter of the cylinder is equal to the diameter of the sphere, which is twice the radius of the sphere. Thus, the diameter of the cylinder is 16 meters and the radius is 8 meters.

Since the height of the cylinder is given as 2x, we can substitute this value into the formula to find the volume:

V = π(8)²(2x) = 128πx

Therefore, the volume of the cylinder is 128πx.

Answer:

I like it when im high marks a lil by and he say he fly but he dono ha ta fly OoOoooOoOoOOoO

Step-by-step explanation:

Answer:

V≈4188.79in³    

Step-by-step explanation:

4.188.79in3

Answer: A

Step-by-step explanation:

Answer:

the first opition is the correct answer

Answer:

[tex]x = p( m - n)[/tex]

Step-by-step explanation:

[tex]m = n + \frac{x}{p} \\ m - n = \frac{x}{p} \\ p(m - n) = \frac{x}{p} \times p \\ \\ x = p(m - n)[/tex]

Answer:

Step-by-step explanation:

Hello!

In descriptive statistics, the median is a measurement of center position. It separates the sample in halves. (bottom 50% from upper 50%)

The manager took a sample of 11 cashiers and recorded the worked hours in a week

To identify the median you have to calculate it's position:

The position is calculated as

PosMe= (n+1)/2= (11+1)/2= 6 cashier

This means that the Median of hours worked is a week observed corresponds to the 6th cashier (after ordering the data from lowest to highest)

If you observe the histogram, the x-axis corresponds to worked hours and the y-axis shows the number of workers.

The workers were already arranged from least hours worked to most hours worked.

The first interval corresponds to 0-10 worked hours and two workers recorded these working times.

The second interval corresponds to 10-20 worked hours and three workers recorded these working times.

In the third interval of 20-30 hours, no workers recorded these working times.

The fourth interval corresponds to 30 - 40 worked hours and 5 workers recorded these working times.

The fifth interval corresponds to 40 - 50 worked hours and only one worker recorded these working hours.

The first five workers were recorded in the first two intervals and the sixth worker was recorded in the fourth interval. So the interval that contains the median number of hours worked is "30 - 40 hours"

I hope this helps!

The interval that contains the median number of hours worked is "30 - 40 hours"

The manager took a sample of 11 cashiers and recorded the worked hours in a week

To identify the median you have to calculate it's position:

The position is calculated as

PosMe= (n+1)/2= (11+1)/2= 6 cashier

The fourth interval corresponds to 30 - 40 worked hours and 5 workers recorded these working times.

The first five workers were recorded in the first two intervals and the sixth worker was recorded in the fourth interval. So the interval that contains the median number of hours worked is "30 - 40 hours"

Learn more about median here

https://brainly.com/question/32773662

#SPJ3

Answer:

The first one is matched with 700,000

The second one is matched with 7

The third one is matched with 70

The fourth one is matched with 70,000

Step-by-step explanation:

Look at where the 7 is in the number, and replace all the digits to the right of it with 0's. Get rid of the digits to the left of the 7, if any

Answer:

1-->1

2-->3

3-->2

4-->4

Step-by-step explanation:

In the first number the 7 is in the the hundred thousands place. In the second the 7 is in the ones place. In the third the 7 is in the tens place. In the fourth the 7 is in the ten thousands place.

Answer:

$15.6

Step-by-step explanation:

one bag= $1.95

8 bags = 8×1.95=15.6

so answer is $15.6.

Answer:

4n-3=5

Step-by-step explanation:

If you read it step by step the product of and a number is basically 4* any variable.( In this case I use n.) Next the beginning part is 3 less than the product part so it is 4n-3. And finally the whole equation is equal to 5 so itis 4n-3=5.

Answer:

uhhh

Step-by-step explanation:

uh I don't see the graph

Answer:

D and B

Step-by-step explanation:

Step-by-step explanation:

15.4% of the nuts are pecans.

0.154x = 77

x = 500

There are 500 pounds of mixed nuts in the batch.

Answer: 40in²

Step-by-step explanation:

To find the area of the shade region, considering the diagram, the diagonal of the rectangle has divided the figure into two equal half. So, one is shaded and the other not shaded. So the shaded region is a right angled triangle,. So the formula for finding the area of a triangle need to be applied.

Area. = 1/2 × b × h

= 1/2 × 10 × 8

= 40in²

Answer:

$99.44 + $1.99 = $101.47

Delivery fee: $6.95

Final bill: $101.47 + 6.95 = $108.42

The final bill will be either $109.43 or $108.42, depending on whether the last-minute item is included in the order.

To calculate the final bill, we need to consider two scenarios: the order without the last-minute item and the order with the last-minute item. First, let's calculate the delivery fee for an order without the last-minute item. Since the order total is $99.48, which is less than $100, the delivery fee will be $9.95. Now, let's calculate the final bill by adding the delivery fee to the order total: $99.48 + $9.95 = $109.43.

Next, let's calculate the delivery fee for an order with the last-minute item. Since the order total will be $101.47 ($99.48 + $1.99), which is more than $100, the delivery fee will be $6.95. To calculate the final bill, we need to add the delivery fee to the updated order total: $101.47 + $6.95 = $108.42.

https://brainly.com/question/37412846

#SPJ2

Answer:

2931 + 51.4n/7 degrees where n is the number of animal from the lion to the zebra in the clockwise direction.

Step-by-step explanation:

We don't have details on the positions of the lion and the zebra prior to revolution but suppose the zebra is n animal away from the lion where n could be in the range of 0 to 6 in the clockwise direction. If n = 0, the zebra is next to the lion in line, and if n = 6, the zebra is right behind the lion.

In angular term, since all 8 animals are evenly spaced, there are 7 space in between them, each of them would span an angle of 360/7 degrees

Then the angular distance between the zebra and the lion is (n+1)360/7 degrees

If the carousel makes between 8 and 9 revolutions then the total angular distance is 8*360 + (n+1)360/7 = 2931 + 51.4n/7 degrees

Answer:

-2970, -3320

Step-by-step explanation:

The carousel makes between 8 and 9 clockwise revolutions

the position of the lion rotated to that of the zebra is two steps

now,

1 revolution = 360 degrees accomplished in 8 steps

1 step = 360/8 = 45 deg

=> position of  lion rotated to zebra = 2 × 45 = 90 deg

if 1 revolution = 360 accomplished in 9 steps

then

1 step = 360/9 = 40 deg

=> position of  lion rotated to zebra = 2 × 40 = 80 deg

since the rotation is in clockwise direction, a negative sign is required

FOR 8 Revolutions

in total the carousel rotates

-[8(360) + 90] degrees

= -2970 degrees

FOR 9 revolution

in total the carousel rotates

-[9(360) + 80] degrees

= -3320 degrees

Answer:

Event is not unusual(p>0.05).

Step-by-step explanation:

Given that :

[tex]p=0.10\\\\n=1100\\\\x=121[/tex]

#The sample proportion is calculated as:

[tex]\hat p=\frac{x}{n}\\\\=\frac{121}{1100}\\\\=0.1100[/tex]

#Mathematically, the z-value is the value decreased by the mean then divided  the standard deviation :

[tex]z=\frac{\hat p- p}{\sqrt{\frac{p(1-p)}{n}}}\\\\\\\\=\frac{0.11-0.10}{\sqrt{\frac{0.10(1-0.10)}{1100}}}\\\\\\=1.1055[/tex]

#We use the normal probability table to determine the corresponding probability;

[tex]P(X\geq 121)=P(Z>1.1055)\\\\=0.1314[/tex]

Hence, the probaility is more than 0.05, thus the event not unusual  and thus  this is not necessarily evidence that the proportion of Americans who are afraid to fly has increased.

Answer:

Mean is 3.2

Median is 3.1

Step-by-step explanation:

a) mean

= (2.5+3.6+3.1+4.3+2.9+2.3+2.6+4.1+3.4)/9

= 28.8/9

= 3.2

b) median: we will arrange in ascending order and pick the middle term.

2.3 2.5 2.6 2.9 3.1 3.4 3.6 4.1 4.3

From the above order, 3.1 is the middle term and is the median

a) The mean reaction time of the 9 subjects is 3.2 seconds.

A mean is an average of a set of values.

The mean is computed by summing the values and then dividing the sum by the number of subjects.

b) The median reaction time for the random sample of 9 subjects to a stimulant is 3.1 seconds.

The median is the middle number in an arranged list of values.  The arrangement takes into consideration their ascending or descending orders.

The median is simple to determine when the list of values is not too long and well-arranged.

Variables    Reaction Times

                       in seconds

1.                         2.5

2.                        3.6

3.                        3.1

4.                       4.3

5.                       2.9

6.                       2.3

7.                       2.6

8.                       4.1

9.                      3.4

Total               28.8

Mean = 3.2 (28.8/9)

6.                       2.3

1.                        2.5

7.                       2.6

5.                       2.9

3.                       3.1

9.                      3.4

2.                      3.6

8.                      4.1

4.                      4.3

Thus, the mean and the median have been calculated.

Learn more about calculating the mean and the median at https://brainly.com/question/452652

Answer:

50

Step-by-step explanation:

add 5 to -25 to get -2/5x by itself.

Answer:

The answer is A.

Step-by-step explanation:

6 3/4 = 27/4

27/4 * 1/3 = 27/12

27/12 = 9/4

Answer: 9/4 cups

To find out how much fruit salad was eaten, convert the mixed number to an improper fraction and multiply by the fraction representing the amount eaten.

To calculate how much fruit salad was eaten, we need to find 1/3 of 6 3/4 cups. First, we convert the mixed number 6 3/4 to an improper fraction by multiplying the whole part (6) by the denominator (4) and adding the numerator (3) to it. This gives us 27/4 cups. Next, we multiply 27/4 by 1/3, which can be simplified to 9/4. So, they ate 9/4 cups of fruit salad.

https://brainly.com/question/35923484

#SPJ2

Answer:

94.41% probability that at least 25 employees in the sample will participate in the optional retirement plan

Step-by-step explanation:

I am going to use the normal approximation to the binomial to solve this question.

Binomial probability distribution

Probability of exactly x sucesses on n repeated trials, with p probability.

Can be approximated to a normal distribution, using the expected value and the standard deviation.

The expected value of the binomial distribution is:

[tex]E(X) = np[/tex]

The standard deviation of the binomial distribution is:

[tex]\sqrt{V(X)} = \sqrt{np(1-p)}[/tex]

Normal probability distribution

Problems of normally distributed samples 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.

When we are approximating a binomial distribution to a normal one, we have that [tex]\mu = E(X)[/tex], [tex]\sigma = \sqrt{V(X)}[/tex].

In this problem, we have that:

[tex]n = 50, p = 0.6[/tex]

So

[tex]\mu = E(X) = np = 50*0.6 = 30[/tex]

[tex]\sigma = \sqrt{V(X)} = \sqrt{np(1-p)} = \sqrt{50*0.6*0.4} = 3.46[/tex]

What is the probability that at least 25 employees in the sample will participate in the optional retirement plan?

Using continuity correction, this is [tex]P(X \geq 25 - 0.5) = P(X \geq 24.5)[/tex], which is 1 subtracted by the pvalue of Z when X = 24.5

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

[tex]Z = \frac{24.5 - 30}{3.46}[/tex]

[tex]Z = -1.59[/tex]

[tex]Z = -1.59[/tex] has a pvalue of 0.0559

1 - 0.0559 = 0.9441

94.41% probability that at least 25 employees in the sample will participate in the optional retirement plan

Answer:

In my opinion I think the answer is C.12/33

Step-by-step explanation:

this would be the answer because...

1. First, add up the amount of boys and girls

21 girls+ 12 boys= 33 total

2. Next, since its asking for the probability for a boys name to de drawn at random, your going to divide 12 by 33

Answer:

it is c i took test good luck

Step-by-step explanation:

sike i lied your a is mine lol

Answer:

c

Step-by-step explanation:

just did it on the assignment

Answer:

$1.9

Step-by-step explanation:

2 pound bag (when he bought) =.30×2=$0.6

when he sells, price is $2.50.

Profit for each bag= $2.5-$0.6=$1.9