The average speed of a volleyball serve is 58 miles per hour. Natalie practiced a new technique to improve her serving speed. Her coach recorded the speed of 41 random serves during practice and found that her average speed using the new technique was 59 miles per hour, with a standard deviation of 2.7 miles per hour.

Part A: State the correct hypotheses if Natalie is trying to prove the new technique is an improvement over the old technique. (2 points)

Part B: Identify the correct test and check the appropriate conditions. (4 points) .

Part C: Carry out the test and determine if there is sufficient evidence at the 0.05 level that Natalie's technique has improved her serve speed. (4 points)

Answer: 10w + 3 + 4.5w = 90

Step-by-step explanation:

a right angle is 90 degrees, so 10w + 3 and 4.5w have to add up to 90 degrees

The equation x⁴/y = 7 represents a relationship of direct proportionality between x and y, where x⁴ and y are inversely proportional to each other.

The equation x⁴/y = 7 represents a relationship between the variables x and y. Specifically, it shows that the fourth power of x divided by y is equal to 7.

This equation can be rewritten as x⁴ = 7y, which means that if we know the value of y, we can determine the corresponding value of x that satisfies the equation. For example, if y = 1, then x⁴ = 7, and taking the fourth root of both sides of the equation gives us x = ± √7.

Conversely, if we know the value of x, we can solve for y by rearranging the equation as y = x⁴/7. This shows that y is directly proportional to x raised to the fourth power, meaning that as x increases, y will also increase, but at a faster rate due to the exponent of 4.

To learn more about equation click on,

https://brainly.com/question/4164028

#SPJ1

Answer:

Let the width of the rectangle be w. Then the length of the rectangle is 5w.

The perimeter of a rectangle is the sum of all four sides. So, the perimeter of the rectangle is 2w+2(5w)=108 cm.

Simplifying the right side of the equation, we get 12w=108 cm.

Dividing both sides of the equation by 12, we get w=9 cm.

Since the width is 9 cm, the length of the rectangle is 5w=5(9)=45 cm.

Therefore, the length of the rectangle is 45 cm and the width is 9 cm.

Answer:

cot(65 deg)

Step-by-step explanation:

cot(x) is the complimentary func. of tan(x) with the relation:

tan x = cot (90 - x) and

cot x = tan (90 - x)

Using the given matrix, the value of -10(T) is

[tex]-10(T) = \left[\begin{array}{cc}-230&380\\-170&60\end{array}\right][/tex]

From the question, we are to carry out the matrix multiplication

From the given information,

The given matrices is:

[tex]T =\left[\begin{array}{cc}23&-38\\17&-6\end{array}\right][/tex]

Now, we are to determine -10(T)

To achieve this, we will multiply each of the element in the given matrix by -10

That is,

-10 ×23 = -230

-10 × -38 = 380

-10 × 17 = -170

-10 × -6 = 60

Thus,

The result of the multiplication will be:

[tex]\left[\begin{array}{cc}-230&380\\-170&60\end{array}\right][/tex]

Hence, the value of -10(T) is

[tex]-10(T) = \left[\begin{array}{cc}-230&380\\-170&60\end{array}\right][/tex]

Learn more on Multiplication of matrices here: https://brainly.com/question/28869656

#SPJ1

Answer:

i believe 67 its somewhat hard to tell but the line seems to be in the middle between 150 and 140

Step-by-step explanation:

since it heats up to 212 then the person lets it cool down for 10 mins the temp goes to 145 (Answer is 67)

The probability of randomly selecting 42 cigarettes with a mean of 7.73 mg or less is:  0.0179

The formula to find the z-score of the given normal distribution is:

z = (x' - μ)/(σ/√n)

where:

x' is sample mean

μ is population mean

σ is standard deviation

n is sample size

We are given:

x' = 7.73 mg

μ = 8.2 mg

σ = 1.45 mg

n = 42

Thus:

z = (7.73 - 8.2)/(1.45/√42))

z = -2.1

From online p-value from z-score calculator, we have:

p = 0.0179

Read more about p-value from z-score at: https://brainly.com/question/25638875

#SPJ1

The resulting matrix from an elementary row operation to get a 1, in row 1 column 1 is:

R₁ = [1 4 -8] and R₂ = [2 4 7]

A rectangular array of numbers or mathematical objects which are arranged in rows and columns is called a matrix. Each row of a matrix is a horizontal sequence of numbers or objects that are separated by commas and enclosed within square brackets, and it represents a vector in the row space of the matrix.

The row operation R₁ - 4 — R₁ will be carried out as follows:

5 - 4 = 1 {row 1 column 1}

9 - 4 = 5 {row column 2}

-4 - 4 = -8 {row column 3}

Therefore, the resulting matrix from an elementary row operation to get a 1, in row 1 column 1 will have:

R₁ = [1 4 -8] and R₂ = [2 4 7]

Read more about matrix row here:https://brainly.com/question/1279486

#SPJ1

The area of the polygon is 33cm²

A polygon is any closed curve consisting of a set of line segments (sides) connected such that no two segments cross.

The area of a polygon is expressed as;

A = 1/2 × p × a

where p is the perimeter of the polygon and a is the apothem.A pentagon is a 5 sides polygon.

Therefore;

Perimeter = 5 × 4.4

= 22cm

apothem = 3cm

area = 1/2 × 22 × 3

= 11× 3

= 33 cm²

therefore the area of the Pentagon in is 33cm²

learn more about area of polygon from

https://brainly.com/question/20110859

#SPJ1

The preparation of the journal entry to record the sale and the settlement of the account receivable is as follows:

January 10, 2022:

Debit Accounts Receivable $16,600

Credit Sales Revenue $16,600

(To record the sale of merchandise on account to Robertsen Co, n/30.)

February 9, 2022:

Debit Notes Receivable $16,600

Credit Accounts Receivable $16,600

(To record the receipt of a 11% promissory note in settlement of account receivable.)

Journal entries refer to the initial records maintained about business transactions.

Journal entries show how the transactions will be posted in the general ledger.

January 10, 2022: Accounts Receivable $16,600 Sales Revenue $16,600

Terms n/30

February 9, 2022: Notes Receivable $16,600 Accounts Receivable $16,600

Learn more about journal entries at https://brainly.com/question/28390337.

#SPJ1

Prepare the journal entry to record the sale and the settlement of the account receivable.

Answer:

The graph should be increasing 2.25 each time

Step-by-step explanation:

Since Oscar buys his lunch in school cafeteria and the cost of 15 school lunches is 33.75

Divide them: 33.75 ÷ 15 =

and will represents the average cost of the lunches in dollar per lunch that is 2.25

Answer:

15.04 (3.s.f)

Step-by-step explanation:

Cos a = adjacent/ hypotenuse

Cos 43 = 11/ x

so,

x= 11 / cos 43

= 15.04

Construct and interpret a 98% confidence interval for the difference in population proportions of females and males who took advanced math courses.

The parameter of interest is the difference in population proportions of females and males who took advanced math courses. We can denote this parameter by p₁ - p₂, where p₁ is the population proportion of females who took advanced math courses, and p₂ is the population proportion of males who took advanced math courses.

To construct a confidence interval for the difference in population proportions, we need to check the following conditions,

The sample of high school students should be a simple random sample.

The sample of high school students should be independent of each other.

Both groups of females and males who took advanced math courses should have at least 10 successes and 10 failures.

The sample proportions of females and males who took advanced math courses can be calculated as follows,

p₁ = 53/150 = 0.353

p₂ = 89/275 = 0.324

The sample size of females and males can also be calculated as follows,

n₁ = 150

n₂ = 275

The standard error of the difference in sample proportions can be calculated as follows,

SE = √[(p₁(1 - p₁))/n₁ + (p₂(1 - p₂))/n₂]

= √[(0.353(1 - 0.353))/150 + (0.324(1 - 0.324))/275] ≈ 0.048

Using a t-distribution with (n₁ + n₂ - 2) degrees of freedom and a 98% confidence level, we can construct a confidence interval for the difference in population proportions as follows:

(p₁ - p₂) ± t*SE

where t is the t-score corresponding to a 98% confidence level and (n₁ + n₂ - 2) degrees of freedom. Using a t-table, we can find that t ≈ 2.33.

Substituting the values into the formula, we get,

(0.353 - 0.324) ± 2.33*0.048

0.029 ± 0.112

True difference in population proportions of females and males who took advanced math courses lies between 0.029 and 0.147.

Part B: Does your interval from part A give convincing evidence of a difference between the population proportions? Explain.

Yes, our interval from part A gives convincing evidence of a difference between the population proportions because it does not contain zero. The interval (0.029, 0.147) is entirely positive, which means that the proportion of females who took advanced math courses is higher than the proportion of males who took advanced math courses. Additionally, the interval does not contain the value of one, which means that the difference in population proportions is not due to chance. Therefore, we can conclude that there is a significant difference in the population proportions of females and males who took advanced math courses.

To know more about Confidence interval here

https://brainly.com/question/24131141

#SPJ1

The correct answer is: D) distance traveled since leaving Bay Town; x ≥ 0

The equation y = -x + 175 represents the distance left to travel to Oak Glen.

In this equation, x is the distance traveled since leaving Bay Town, and y is the distance left to reach Oak Glen.

The domain represents the possible values of x, which is the distance traveled since leaving Bay Town.

Since distance traveled cannot be negative, the domain is x ≥ 0. Therefore, the correct answer is:

D) distance traveled since leaving Bay Town; x ≥ 0

Read more about domain and range here:

https://brainly.com/question/26098895

#SPJ1

The question in English is:

The distance between Bay Town and Oak Glen is 175 miles. If the equation y = -x +175 represents the distance to go to Oak Glen, what does the domain represent? What is the domain?

Answer:1020 ft (squared)

Step-by-step explanation:

Base width 1 (28 ft) x Base width 2 (40 ft) x height (6 ft) = 1020 ft (squared)

Answer:

234.8525 square inches

Step-by-step explanation:

To find the total area of construction paper needed for the project, we need to find the area of each rectangle and add them together.

For the first rectangle, the dimensions are:

Length = 9 inches

Width = 14 1/3 inches

Area of the first rectangle = Length x Width

Area of the first rectangle = 9 inches x (43/3) inches

Area of the first rectangle = 9 inches x 14.33 inches

Area of the first rectangle = 128.97 square inches (rounded to two decimal places)

For the second rectangle, the dimensions are:

Length = 10 1/4 inches

Width = 10 1/3 inches

Area of the second rectangle = Length x Width

Area of the second rectangle = (41/4) inches x (31/3) inches

Area of the second rectangle = 10.25 inches x 10.33 inches

Area of the second rectangle = 105.8825 square inches (rounded to four decimal places)

Therefore, the total area of construction paper needed for the project is:

Total area = Area of first rectangle + Area of second rectangle

Total area = 128.97 square inches + 105.8825 square inches

Total area = 234.8525 square inches (rounded to four decimal places)

Therefore, Alexia needs a total of approximately 234.8525 square inches of construction paper for her project.

Answer:

Step-by-step explanation:

first, take 1/2+1/3 + 1/4+2/3

1/2+1/3=5/6 , 1/4+2/3=11/12

5/6+11/12=22/12

2/5-4=-18/5

-18/5*5/6=-3

22/12/3=22*3/12

=11/2

11/2/3/7=11/2*7/3

=77/6=12.8

If we substitute x = 21 into the equation Y = 25 - 2x, we get:

Y = 25 - 2(21)

Y = 25 - 42

Y = -17

Therefore, if x = 21, then Y = -17.

If we substitute x = 19 into the equation Y = 25 - 2x, we get:

Y = 25 - 2(19)

Y = 25 - 38

Y = -13

Therefore, if x = 19, then Y = -13.

I can't see the chart...

The array that represents the total number of miles is X = 12

Given that;

Selena ran 4 miles per day

And she ran for 3 different days

Let the total miles she ran = X

therefore

X =  miles of 1st day  + miles of 2nd day  + miles of 3rd day

⇒ X = 4 + 4 + 4

⇒ X = 12 miles

Thus the symbolic form of miles Selena ran is,

X = 12.

To learn more about multiples visit:

https://brainly.com/question/11799672

#SPJ1

Answer:

Step-by-step explanation:

1) Find the upper bound of the confidence interval:

Upper bound = sample mean + margin of error

= 172.6 + 4.8

= 177.4

2) Find the lower bound of the confidence interval:

Lower bound = sample mean - margin of error

= 172.6 - 4.8

= 167.8

3) Estimate the total number of text messages sent in a month:

Total number of text messages sent = (number of students in the population / number of students in the sample) x sample mean

        = (3000 / 250) x 172.6

        = 2071.2

Therefore, the estimated number of text messages sent in a month is 2071.2, with a 95% confidence interval between 167.8 and 177.4 text messages.

Answer:

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

Find lower bound:

Find upper bound:

Lower bound:

Upper bound:

The estimated number of text messages sent in a month for all 3000 high-school students in the city is:

The equation that represents the consecutive odd numbers whose product is 63 is; (x + 9) (x + 7) = 0

Odd numbers have special properties and relationships to other numbers, which make them important in mathematics. For instance, the sum of two odd numbers and the difference between two odd numbers both always equal one.

We can see that we can solve the double brackets by equation them to zero so we have that;

(x + 9) (x + 7) = 0

x = -9

x = -7

Thus;

(-9) (-7) = 63

Learn more about odd numbers:https://brainly.com/question/30806559

#SPJ1

To find the estimated amount John needs to save to buy the bike, we can subtract the amount he already has saved from the cost of the bike:

Estimated amount = Cost of bike - Amount already saved

Estimated amount = $337 - $103

Estimated amount = $234

Therefore, John needs to save an estimated $234 more to buy the bike.

Answer:

John needs to save about $234 more to buy the bike. Note that this is an estimate, as we do not know if John will need to pay any taxes or additional fees when purchasing the bike.

Step-by-step explanation:

To find out how much more John needs to save to buy the bike, we can subtract the amount he has already saved from the cost of the bike:

337 - 103 = 234

Therefore, John needs to save about $234 more to buy the bike. Note that this is an estimate, as we do not know if John will need to pay any taxes or additional fees when purchasing the bike.

The exponential function representing the number of bacteria t hours after the initial measurement is B(t) = 15 (4[tex])^t[/tex].

The function B(t) can be represented by an exponential function of the form:

B(t) = a[tex]b^t[/tex]

where 'a' is the initial number of bacteria and 'b' is the growth factor or rate at which the number of bacteria quadruples.

Given that the initial number of bacteria is 15 and the number of bacteria quadruples every hour, we can express 'b' as:

b = 4¹ = 4

Substituting the values of 'a' and 'b' in the general form of exponential function, we get:

B(t) = 15 (4[tex])^t[/tex]

Therefore, the exponential function representing the number of bacteria t hours after the initial measurement is B(t) = 15 (4[tex])^t[/tex].

Learn more about Exponential Function here:

https://brainly.com/question/14355665

#SPJ1

The population proportion of items manufactured that are defective is estimated to be between 0.137 and 0.037 with a 95% confidence level.

The sample proportion, denoted as ^p, is the proportion of a certain characteristic or outcome in a sample. It is calculated by dividing the number of individuals in the sample that exhibit the characteristic or outcome of interest by the total number of individuals in the sample.

It is an estimate of the population proportion, denoted as p, which represents the proportion of the same characteristic or outcome in the entire population.

Here we have

The sample proportion (^) of defective items is not provided in the question.

Hence, let's assume that the sample proportion (^) of defective items is 0.05 (i.e., 5% as specified in the question).

The sample size is 50, and the sample proportion (^) is 0.05.

The question is asking for the population proportion of items manufactured that are defective (P).

Use the sample proportion (^) and the sample size to calculate the margin of error and construct a confidence interval.

Assuming a 95% confidence level, we can use the following formula to calculate the margin of error:

Margin of error = 1.96 × √(^×(1⁻^)/n)

Substituting the values, we get:

Margin of error = 1.96 × √(0.05 × (1 - 0.05)/50) = 0.087

To construct the confidence interval, we add and subtract the margin of error from the sample proportion:

Confidence interval = ^ ± margin of error

Confidence interval = 0.05 ± 0.087

Confidence interval = (0.137, 0.037)

Therefore,

The population proportion of items manufactured that are defective is estimated to be between 0.137 and 0.037 with a 95% confidence level.

Learn more about Sample Proportions at

https://brainly.com/question/29912751

#SPJ1

Answer:

x= 3 cm

Explanation:

I am bad at it

For A∩B , shade the middle common part in the Venn diagram.

What is Venn diagram?

Using circles to represent relationships between objects or limited groupings of objects, a Venn diagram is one example. Circles that overlap share certain characteristics, whereas circles that do not overlap do not. Venn diagrams are useful for showing how two concepts are related and different visually.

Here the given Venn diagram contains two sets A and B.

The A intersection B or A∩B means , common elements in both A and B.

So we have shade the middle part of Venn Diagram.

To learn more about Venn Diagram refer the below link

https://brainly.com/question/28060706

#SPJ9

The area between the curves is 61.5 square units.

To compute the area between the curves y = 9x and y = x^2 - 10, find the points of intersection between the curves.

Setting the two equations equal to each other:

x^2 - 10 = 9x

Move all to one side:

x^2 - 9x - 10 = 0

Factor the quadratics:

(x - 10)(x + 1) = 0

So, the points of intersection are x = -1 and x = 10.

Now, determine which curve is above the other in the interval between -5 and 3. Evaluating the y-coordinates of each curve at a point in this interval, say x = 0.

y = 9x, y = 0 at x = 0, so the curve passes across the origin.

y = x^2 - 10, y = -10 at x = 0.

Therefore, the curve y = 9x is above y = x^2 - 10 in the interval [-5, 3].

To compute the area between the curves, take the integral of the top curve minus the integral of the bottom curve over the interval of intersection:

∫(-1 to 3) [9x - (x^2 - 10)] dx

Simplify:

∫(-1 to 3) [ -x^2 + 9x + 10] dx

Then, integrate each term of the polynomial:

[ (-1/3) x^3 + (9/2) x^2 + 10x ] evaluated from x = -1 to x = 3

Plug into the limits of integration and then simplify:

= [ (81/2) - (19/3) ] - [ (-1/3) - (17/2) ]

= 61.5

Therefore, the area between the curves is 61.5 square units.

learn more about polynomial: https://brainly.com/question/2833285

#SPJ1

By ASA (Angle-Side-Angle) congruence, triangle ABC is congruent to triangle DEF.

Instructions to draw the routes:

Draw the x-axis and y-axis to create a coordinate plane.

Mark the starting point of Zari's run as (0,0) on the coordinate plane.

From (0,0), move 2 units north to reach (0,2).

From (0,2), move 4 units east to reach (4,2).

From (4,2), move directly back to the starting point (0,0) using the shortest route.

Mark the starting point of Taye's run as (0,0) on the coordinate plane.

From (0,0), move 2 units west to reach (-2,0).

From (-2,0), move 4 units south to reach (-2,-4).

From (-2,-4), move directly back to the starting point (0,0) using the shortest route.

Instructions to prove that the two triangles are congruent using ASA:

Label the vertices of Zari's triangle as A (0,0), B (4,2), and C (0,0).

Label the vertices of Taye's triangle as D (0,0), E (-2,-4), and F (0,0).

Show that angle A and angle D are congruent because they are both right angles (90 degrees).

Show that segment AB and segment DE are congruent because they both have a length of 4 units.

Show that segment AC and segment DF are congruent because they both have a length of 2 units.

To learn more about the congruent;

https://brainly.com/question/12413243

#SPJ1

Answer:

  a) 10:30 a.m.

  b) 75 km/h

Step-by-step explanation:

You want to know the leaving time and speed of a car from Woodlands to Muar if it left half an hour later and arrived half an hour earlier than a coach that traveled the 150 km distance at a speed of 50 km/h and arrived at 1 p.m..

The travel time of the coach is found from the relation ...

  time = distance/speed

  time = (150 km)/(50 km/h) = (150/50) h = 3 h

Then the coach left Woodlands at ...

  1 pm -3 h = 10 am

The car left half an hour later than the coach, so left at 10:30 a.m..

The car arrived at Muar at 12:30 p.m. so had a travel time of ...

  12:30 -10:30 = 2 h

The speed over the 150 km distance is given by ...

  speed = distance/time

  speed = (150 km)/(2 h) = (150/2) km/h = 75 km/h

The average speed of the car was 75 km/h.

__

Additional comment

The car passed the coach at 11:30 a.m., when both had covered half the distance.