The desired percentage of Silicon Dioxide (SiO2) in a certain type of aluminous cement is 5.5. To test whether the true average percentage is 5.5 for a particular production facility, 16 independently obtained samples are analyzed and a sample mean of 5.25 was obtained. Suppose that the percentage of SiO2 in a sample is normally distributed with a sigma of 0.3. Does this indicate conclusively that the true average is smaller than 5.5? Carry the procedure at a 0.01 significance level. Use only the P-Value approach. State H0 and Ha

Answers

Answer 1

Answer:

a)  Null hypothesis : H₀ : μ = 5.5

 Alternative Hypothesis : H₁ : μ < 5.5

b) The test statistic

        |t| = |-3.33| = 3.33

c) P - value lies between in these intervals

0.001 < P < 0.005

Step-by-step explanation:

Step( i ):-

Given data the Population mean 'μ' = 5.5

The small sample size 'n' = 16

The sample mean (x⁻) = 5.25

Given the  percentage of SiO2 in a sample is normally distributed with a sigma of 0.3.

Null hypothesis : H₀ : μ = 5.5

 Alternative Hypothesis : H₁ : μ < 5.5

 Level of significance ∝ = 0.01

Step(ii):-

 The test statistic

                              [tex]t = \frac{x^{-} -mean}{\frac{S.D}{\sqrt{n} } }[/tex]

                             [tex]t = \frac{5.25 -5.5}{\frac{0.3}{\sqrt{16} } }[/tex]

On calculation , we get

                            t = -3.33

                           |t| = |-3.33| = 3.33

Step(iii):-

P - value

The degrees of freedom γ = n-1 = 16-1 =15

The calculated value t = 3.33 (check t-table) lies between the 0.001 to 0.005

0.001 < P < 0.005

Condition(i)

P - value < ∝ then reject H₀

Condition(ii)

P - value > ∝ then Accept H₀

we observe that  0.001 < P < 0.005

P- value < 0.01

we rejected  H₀

(or)

The tabulated value  = 2.60 at 0.01 level of significance with '15' degrees of freedom

The calculated value t = 3.33 > 2.60 at 0.01 level of significance with '15' degrees of freedom

The null hypothesis is rejected

Conclusion:-

Accepted Alternative hypothesis H₁

The Claim that the true average is smaller than 5.5

             

The Desired Percentage Of Silicon Dioxide (SiO2) In A Certain Type Of Aluminous Cement Is 5.5. To Test

Related Questions

A footbridge has a span of 54 feet. A sign is
to be placed exactly halfway across the bridge. How far will the center of the sign be from each end of the bridge?

Answers

Answer:

27

Step-by-step explanation:

Because if it is halfway, that means

halfway=1/2

1/2=1/2 of 54

54/2 or 1/2 of 54=27

PLS MARK ME BRAINLIEST I NEED IT PLEASE

The center of the sign will be 27 feet apart from both ends of the bridge.

Given that,
A footbridge has a span of 54 feet. A sign is to be placed exactly halfway across the bridge. How far will the center of the sign be from each end of the bridge is to be determined.

What is arithmetic?

In mathematics, it deals with numbers of operations according to the statements. There are four major arithmetic operators, addition, subtraction, multiplication, and division,

Here,

Since the bridge is 54 feet long,
Now at the center of the bridge, a sign is placed,
So the distance of sign from both ends is equal to half of the total length of the bridge. i.e.
= 54 / 2
= 27

Thus, the center of the sign will be 27 feet apart from both ends of the bridge.

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Two terms of an arithmetic sequence are a12=70 and a30=124. Write an explicit rule for the nth term.

Answers

Answer:

Tn = 34-3n

Step-by-step explanation:

The formula for calculating the nth term of an arithmetic sequence is given as;

Tn = [tex]a+(n-1)d[/tex]

a is the first term

n is the number of terms

d is the common difference

If  two terms of an arithmetic sequence are a12=70 and a30=124 then;

T12 = a+(12-1)d = 70

T12 = a+11d = 70...(1)

T30 = a+(30-1)d = 124

T30 = a+29d = 124...(2)

Solving equation 1 and 2 simultaneously to get a and d;

Taking the difference of both equation we have;

29d - 11d = 124-70

18d = 54

d = 54/18

d = 3

Substituting d=3 into equation 1 to get the value of 'a' we have;

a+11(3) = 70

a+33=70

a = 70-33

a = 37

To get the explicit rule for the nth term of the sequence, we will use the formula Tn = a+ (n-1)d where a = 37, d =3

Tn = 37+(n-1)3

Tn = 37+3n-3

Tn = 34-3n

This gives the required nth term

To the nearest tenth of a cubic centimeter, what is the volume of
the sphere if r = 17 cm?

Answers

20579.53 cubic centimeters.

Answer:

V≈20579.53

Step-by-step explanation:

[tex]V=\frac{4}{3} \pi r^3[/tex]

During Ashland High School basketball games, the snack bar sells both cheese and pepperoni pizza slices. Last night, the snack bar sold 143 slices of pizza. They sold 10 times as many pepperoni slices as cheese slices.

How many slices of cheese pizza did the snack bar sell last night?

slices of cheese pizza

Answers

Answer:

  13 slices of cheese pizza

Step-by-step explanation:

Consider grouping the slices so there are 10 pepperoni and 1 cheese in each group of 11. Then 143 slices represents 143/11 = 13 groups. Since there is 1 cheese slice in each group, ...

  13 slices of cheese pizza were sold

OMG THIS QUESTION IS SO HARD WILL RATE IF U GET IT

Answers

Answer:

19.5 in²

Step-by-step explanation:

Area of rhombus tile = side × height

Area = 3 × 6.5

Area = 19.5 in²

A rhombus, like any parallelogram, has area equal to base times height,

that's 3×6.5 = 19.5 square inches

Answer: 19.5

Figure A is translated 3 units right and 2 units up. The translated figure is labeled figure B. Figure B is reflected over the x-axis. The reflected figure is labeled figure C. Which best explains why figure A is congruent to figure C? On a coordinate plane, triangle A has points (1, negative 2), (3, negative 2), (3, negative 5). Triangle B has points (4, 0), (6, 0), (6, negative 3). Triangle C has points (4, 0), (6, 0), (6, 3). A Is congruent to B and B Is congruent to C A Is congruent to A, B Is congruent to B, C Is congruent to C Each triangle is a right triangle. Each triangle is an isosceles triangle.

Answers

Answer:

A Is congruent to B and B Is congruent to C

Step-by-step explanation:

Let's look at the answer choices:

A: "A Is congruent to B and B Is congruent to C"

Well, clearly, if A ≅ B and B ≅ C, then by the transitive property, we can say that A ≅ C. So, A is very likely correct.

B: "A Is congruent to A, B Is congruent to B, C Is congruent to C"

Just because A is congruent to itself (and same with B and C) doesn't necessarily mean that they're congruent to each other. So, B is wrong.

C: "Each triangle is a right triangle."

Again, there are so many right triangles out there with different dimensions. For example, there are some with sides 3, 4, and 5, and others with sides 5, 12, and 13. They are not congruent, however. So, rule out C.

D: "Each triangle is an isosceles triangle."

This is just like choice C since there are so many variations of isosceles triangles. So D is wrong.

The answer is thus A.

Answer:

First one:

A Is congruent to B and B Is congruent to C

Step-by-step explanation:

Since B is obtained by translating A, it has the same measure angles and sides as A, hence B is congruent to A

C is obtained by reflecting B, which doesn't alter the measure of sides and angles, so C is congruent to B

Therefore by transition, C is congruent to A

David is preparing a report to show

Answers

Answer:

cool?

who's david den

Step-by-step explanation:

Answer:

He shoud use a table or chart.

Step-by-step explanation:

I answered this question before

Sara goes on a slingshot ride in an amusement park. She is strapped into a spherical ball that has a radius of centimeters. What is the volume of air in the spherical ball? Use this formula: , where r is the sphere’s radius.
A.

B.

C.

D.

Answers

Answer:

A. 4×π×3²×[tex]10^{6}[/tex]

Step-by-step explanation:

r = 3×10² = 3×100 = 300

[tex]\frac{4}{3}[/tex]×π×300³=

[tex]\frac{4}{3}[/tex]×π×27,000,000=

[tex]\frac{108,000,000}{3}[/tex]×π=

36,000,000π

Answers solved:

A. 36,000,000π

B. 108,000,000π

C. 3,600,000π

D. 32,400,000π

The solution is Option A.

The volume of the air in the spherical ball is given by the equation

V = 4π ( 3 )² ( 10 )⁶ cm³

What is a Sphere?

A sphere is symmetrical, round in shape. It is a three dimensional solid, that has all its surface points at equal distances from the center. It has surface area and volume based on its radius. It does not have any faces, corners or edges.

The Surface Area of a Sphere = 4πr²

The Volume of a Sphere = ( 4/3 ) πr³

where r is the radius of the sphere

Given data ,

Let the volume of the sphere be represented as V

Now , the radius of the spherical ball be r

The value of r = 3 ( 10 )² cm

So , the volume of the spherical ball = ( 4/3 ) πr³

Substituting the values in the equation , we get

Volume of the spherical ball V = ( 4/3 ) x π x [ 3 ( 10 )² ]³

On simplifying the equation , we get

Volume of the spherical ball V = ( 4/3 ) x π x ( 3 )³ ( 10 )⁶

Volume of the spherical ball V = 4 x π x ( 3 )² ( 10 )⁶

Therefore , the value of V is 4π ( 3 )² ( 10 )⁶

Hence , the volume of the spherical ball is 4π ( 3 )² ( 10 )⁶

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lan ran 24 laps in a charity run and then walked 0.2 kilometer to the presentation table the total; distance lan traveled was 29.6 kilometer what was the distance of each lap explain how you solve the problem

Answers

Answer:

Step-by-step explanation:

1.225km is equal to each laps

Step-by-step explanation:

Since Kristy total distance traveled = 29.6km

And Kristy ran 24 laps and later walk 0.2km. it simply implies that

Total distance traveled = distance covered running + distance covered walking

Since we know that

Total distance traveled = 29.6km

distance covered running = 24 laps

distance covered walking = 0.2km

Distance covered running in km = total distance traveled - distance covered walking

Distance covered running in km = 29.6km - 0.2km = 29.4km.

To now find the distance for each lap.

Since we have:

Distance covered running in km = 29.4km.

Distance covered running in lap = 24 laps

i.e

24 laps = 29.4km

1 lap = x

Use cross-multiple

24 laps * x = 29.4km × 1 lap

x = 29.4km / 24

x = 1.225km

Therefore

1.225km is equal to each laps.

Answer:1.225km is equal to each laps

Step-by-step explanation:

i need help with this problem x/56=7/8 Thank you

Answers

[tex] \dfrac{x}{56} = \dfrac{7}{8} \\ x = \dfrac{56 \times 7}{8} \\ x = 49[/tex]

6
An ordinary fair dice is thrown once.
(a) On the probability scale mark with a cross (X) the probability ti
the dice lands on an even number.
1
2
(b) Write down the probability that the dice lands on a number les
than 3.​

Answers

Answer:

(a) 1/2(b) 1/3

Step-by-step explanation:

(a) 3 of the 6 numbers on the die are even, so the probability that one of them will show is 3/6 = 1/2.

__

(b) 2 of the 6 numbers on the die are less than 3, so the probability that one of them will show is 2/6 = 1/3.

What is the number of possible permutations of 5 objects taken 2 at a time? A. 10 B. 20 C. 60 D. 120

Answers

Answer:

B. 20

Step-by-step explanation:

5P2 is equal to 20 using the permutation formula.

Drag each tile to the correct box. Not all tiles will be used.
Arrange the equations in the correct sequence to find the inverse of f(x) = y = 3x / 8 + x​

Answers

Answer:

Inverse of f(x)

               [tex]f^{l} (x) = \frac{8 x}{3-x}[/tex]

Step-by-step explanation:

Explanation:-

Step(i):-

Given the function

                        [tex]f(x) = \frac{3 x}{8+x}[/tex]

Given function is one-one and onto function

Hence f(x) is bijection function

                   [tex]y = f(x) = \frac{3 x}{8+x}[/tex]

now cross multiplication, we get

            ( 8+x)y = 3 x

             8 y + x y = 3 x

             8 y = 3 x - x y

taking Common 'x' we get

            x (3 - y) = 8 y

                   [tex]x = \frac{8 y}{3-y}[/tex]

Step(ii):-

The inverse function

                 [tex]x = \frac{8 y}{3-y} = f^{l}(y)[/tex]

The inverse function of x

                  [tex]f^{l}(x) = \frac{8 x}{3-x}[/tex]

Final answer:-

Inverse of f(x)

               [tex]f^{l} (x) = \frac{8 x}{3-x}[/tex]

Equations
What is the solution of the system of linear equations?
-3x + 4y = -18
2x - y = 7

(-2,-3)
(-2,3)
(2, -3)
(2, 3)​

Answers

Answer:

Step-by-step explanation:

-3x + 4y = -18

8x - 4y =   28

5x = 10

x = 2

4 - y = 7

-y = 3

y = -3

(2, -3)

The solution of the system of linear equations given is (2,-3), the correct option is C.

What is System of Linear Equation?

The system of linear equation is set of equations which have a common solution.

The equations are

-3x+4y = -18

2x-y =7

The linear equations can be solved using substitution method

y = 2x -7 from equation 2 will be substituted in equation 1

-3x +4 ( 2x -7) = -18

-3x +8x -28 = -18

5x = 10

x = 2

y = 2 * 2 -7 = -3

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how many tenths are in 4600​

Answers

Answer:

4600 tenths as a Fraction

Since 4600 tenths is 4600 over ten, 4600 tenths as a Fraction is 4600/10.

4600 tenths as a Decimal

If you divide 4600 by ten you get 4600 tenths as a decimal which is 460.00.

4600 tenths as a Percent

To get 4600 tenths as a Percent, you multiply the decimal with 100 to get the answer of 46000 percent.

4600 tenths of a dollar

First we divide a dollar into ten parts where each part is 10 cents. Then we multiply 10 cents with 4600 and get 46000 cents or 460 dollars and 0 cents.

Step-by-step explanation:

Hope this helped!

Stay safe!!!

Answer:

Step-by-step explanation:

To answer this, multiply 4600 by 10:  46000.  There are 46000 tenths in 4600.

A slot machine has 3 dials each dial has 30 positions one of which is jackpot. To win jackpot all three dials must be in jackpot position. Assuming each play spins the dials and stops each independently and randomly, what are the odds of one play winning the jackpot

Answers

Answer:

3/90

Step-by-step explanation:

1 slot  is 1/30

2 slot is 1/30

3 slot is 1/30

this gives you that 3/90 when you had them

Answer:

D)  1/(30×30×30) = 1/27000 = 0.00003 or 0.003%

Step-by-step explanation:

will mark the branliest to first one who answers

Answers

Answer:

3 1/4

Step-by-step explanation:

3/4 + (1/3 ÷1/6) - (-1/2)

Subtracting a negative is adding

3/4 + (1/3 ÷1/6) +1/2

Parentheses first

Copy dot flip

3/4 + (1/3 * 6/1) +1/2

3/4 + 2 + 1/2

Get a common denominator

3/4 + 2 + 2/4

2 + 5/4

2 + 4/4 +1/4

2+1 + 1/4

3 1/4

Please help ASAP! Will give BRAINLIEST! Please read the questionTHEN answer correctly! No guessing.

Answers

Answer:D

Step-by-step explanation:

(4/5)^0

4^0/5^0=1/1=1

Im a parent for a 5th grader and don't remember this, plz help?
Again,
Josh wants to make 5 airplane propellers. he needs 18 centimeters of wood for each propeller. how many centimeters of wood will he use? How can I help him understand this problem.

Answers

Answer:

90 cm.

Step-by-step explanation:

One airplane propeller needs 18 centimetres of wood.

Josh wants to make 5 of them.

So, we would have to take the '18' centimetres of wood and multiply by 5 to get the total for all 5 pieces.

[tex]\text{Number of Propellers} * 18 \text{ Centimetres}[/tex]

[tex]5 * 18 = 90[/tex]

Josh should need 90 centimetres of wood total to make 5 airplane propellers.

So since josh wants to make 5 airplane propellers and he would need 18 centimeters of wood for each propeller. He would need 90cm of wood. When I was younger I would just add. For this problem I would just do this. 18+18+18+18+18=90. I would suggest doing this if your child isn’t very good a multiplication. I’m sorry if this is wrong or something it’s been 7 years since I have been to the 5th grade.

Answer=90

Two samples each of size 20 are taken from independent populations assumed to be normally distributed with equal variances. The first sample has a mean of 43.5 and standard deviation of 4.1 while the second sample has a mean of 40.1 and standard deviation of 3.2. A researcher would like to test if there is a difference between the population means at the 0.05 significance level. What can the researcher conclude?

Answers

Answer:

[tex]t=\frac{(43.5 -40.1)-(0)}{3.678\sqrt{\frac{1}{20}+\frac{1}{20}}}=2.923[/tex]

The degrees of freedom are

[tex]df=20+20-2=38[/tex]

And the p value is given by:

[tex]p_v =2*P(t_{38}>2.923) =0.0058[/tex]

Since the p value for this cae is lower than the significance level of 0.05 we have enough evidence to reject the null hypothesis and we can conclude that the true means for this case are significantly different

Step-by-step explanation:

When we have two independent samples from two normal distributions with equal variances we are assuming that  

[tex]\sigma^2_1 =\sigma^2_2 =\sigma^2[/tex]

And the statistic is given by this formula:

[tex]t=\frac{(\bar X_1 -\bar X_2)-(\mu_{1}-\mu_2)}{S_p\sqrt{\frac{1}{n_1}+\frac{1}{n_2}}}[/tex]

Where t follows a t distribution with [tex]n_1+n_2 -2[/tex] degrees of freedom and the pooled variance [tex]S^2_p[/tex] is given by this formula:

[tex]S^2_p =\frac{(n_1-1)S^2_1 +(n_2 -1)S^2_2}{n_1 +n_2 -2}[/tex]

The system of hypothesis on this case are:

Null hypothesis: [tex]\mu_1 = \mu_2[/tex]

Alternative hypothesis: [tex]\mu_1 \neq \mu_2[/tex]

We have the following data given:

[tex]n_1 =20[/tex] represent the sample size for group 1

[tex]n_2 =20[/tex] represent the sample size for group 2

[tex]\bar X_1 =43.5[/tex] represent the sample mean for the group 1

[tex]\bar X_2 =40.1[/tex] represent the sample mean for the group 2

[tex]s_1=4.1[/tex] represent the sample standard deviation for group 1

[tex]s_2=3.2[/tex] represent the sample standard deviation for group 2

First we can begin finding the pooled variance:

[tex]\S^2_p =\frac{(20-1)(4.1)^2 +(20 -1)(3.2)^2}{20 +20 -2}=13.525[/tex]

And the deviation would be just the square root of the variance:

[tex]S_p=3.678[/tex]

The statistic is givne by:

[tex]t=\frac{(43.5 -40.1)-(0)}{3.678\sqrt{\frac{1}{20}+\frac{1}{20}}}=2.923[/tex]

The degrees of freedom are

[tex]df=20+20-2=38[/tex]

And the p value is given by:

[tex]p_v =2*P(t_{38}>2.923) =0.0058[/tex]

Since the p value for this cae is lower than the significance level of 0.05 we have enough evidence to reject the null hypothesis and we can conclude that the true means for this case are significantly different

Using the t-distribution, as we have the standard deviation for the sample, it is found that the researcher can conclude that there is a difference between the population means at the 0.05 significance level.

What are the hypothesis tested?

At the null hypothesis, it is tested if there is no difference, that is:

[tex]H_0: \mu_1 - \mu_2 = 0[/tex]

At the alternative hypothesis, it is tested if there is a difference, that is:

[tex]H_a: \mu_1 - \mu_2 \neq 0[/tex]

What is the mean and the standard error of the distribution of differences?

For each sample, we have that they are given by

[tex]\mu_1 = 43.5, s_1 = \frac{4.1}{\sqrt{20}} = 0.9168[/tex]

[tex]\mu_2 = 40.2, s_2 = \frac{3.2}{\sqrt{20}} = 0.7155[/tex]

Hence, for the distribution of differences, the mean and the standard error are given by:

[tex]\overline{x} = \mu_1 - \mu_2 = 43.5 - 40.2 = 3.3[/tex]

[tex]s = \sqrt{s_1^2 + s_2^2} = \sqrt{0.9168^2 + 0.7155^2} = 1.163[/tex]

What is the test statistic?

It is given by:

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

In which [tex]\mu = 0[/tex] is the value tested at the null hypothesis, hence:

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

[tex]t = \frac{3.3 - 0}{1.163}[/tex]

[tex]t = 2.84[/tex]

What is the decision?

Considering a two-tailed test, as we are testing if the mean is different of a value, with a significance level of 0.05 and 20 + 20 - 2 = 38 df, the critical value is of [tex]|z^{\ast}| = 2.0244[/tex].

Since the absolute value of the test statistic is greater than the critical value, it is found that the researcher can conclude that there is a difference between the population means at the 0.05 significance level.

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Junior bought a bag of mixed fruit snacks. The flavors in the bag are 4 strawberry, 3 cherry, and 5 grape. If he chooses one fruit snack at random, what it the probability of the first one being grape?

Answers

Answer:I believe it would be 5/12

Step-by-step explanation:

You add all of them up then since it's 5 grapes and in total there is 12 fruit snacks. It should be 5 grapes of 12 fruit snacks in the bag.

A celebrity called Wayne East has been having some money problems recently. He is thinking of investing in the greatest record in the world, and wants to know how the value will change over time. He has an exponential regression model where his predictor is time in months, and response variable is money, measured in thousands of dollars. The alpha value is 4.2, and beta is 1.03. Based on this model, how much money (in thousands) will he have after six months

Answers

Answer:

Wayne west would have $5,015 in six months

Step-by-step explanation:

The formula for exponential regression model is y = αβˣ

Where y is amount of money in 1000 dollars

           x is time in months

We are given that α = 4.2 and  β = 1.03 and x = 6 months

Therefore, based on this model, y = αβˣ, the amount he would have in 6 months, y = [tex]4.2*(1.03) ^{6}[/tex]

y = 5.015 × 1000 = $ 5,015

what is the cube root of 1

Answers

Answer:

1.

Step-by-step explanation:

∛1= 1.

It can also be seen as:

1×1×1= 1.

In ΔXYZ, the measure of ∠Z=90°, the measure of ∠X=57°, and XY = 8 feet. Find the length of YZ to the nearest tenth of a foot.

Answers

Answer:

21

Step-by-step explanation:

Answer:

6.7

Step-by-step explanation:

What is the area of the triangle

Answers

Answer:

A. 6 inchesssssssss

Answer:

6

Step-by-step explanation:

Suppose you had to
guess on a four-choice
multiple-choice test and
were given four questions.
Find the binomial
probability distribution.
( + ) ℎ =
4 = 0.25

Answers

Answer:

For 0 correct answer [tex]^4c_0p^0q^{4-0}[/tex]

For 1 correct answer [tex]^4c_1p^1q^{4-1}[/tex]

For 2 correct answer [tex]^4c_2p^0q^{4-2}[/tex]

For 3 correct answer [tex]^4c_3p^1q^{4-3}[/tex]

For 4 correct answer [tex]^4c_4p^1q^{4-4}[/tex]

Step-by-step explanation:

It is given that there are 4 questions n = 4

Number of choices is 4

So probability of getting correct answer [tex]=\frac{1}{4}[/tex]

Probability of getting incorrect answer [tex]=1-\frac{1}{4}=\frac{3}{4}[/tex]

Probability distribution is given by [tex]^nc_rp^rq^{n-r}[/tex]

Therefore probability distribution of 0 correct answer

[tex]^4c_0p^0q^{4-0}[/tex]

Therefore probability distribution of 1 correct answer

[tex]^4c_1p^1q^{4-1}[/tex]

Therefore probability distribution of 2 correct answer

[tex]^4c_2p^0q^{4-2}[/tex]

Therefore probability distribution of 3 correct answer.

[tex]^4c_3p^1q^{4-3}[/tex]

Therefore probability distribution of 4 correct answer.

[tex]^4c_4p^1q^{4-4}[/tex]

A music professor offers his 40 students the option of coming to an additional rehearsal session the week before their juries (musical final exams.) In order to decide whether these extra sessions actually help students, he keeps track of who attends them and compares their jury scores to those of students who did not schedule extra sessions. This study is a(n): A) matched pairs design. B) randomized block design. C) nonrandomized experiment. D) observational study. E) completely randomized experiment.

Answers

Answer:

D. Observational Study

Explanation:

An observational  study is one in which all the participants are subjected to a common treatment and then compared to people who did not receive the same treatment. This is the case with the students who where subjected to the same treatment; an additional rehearsal session. They are then observed by the professor and compared to those who did not participate in the experiment.  

This is also an example of a cohort observational study. A cohort observational study is one in which all the participants have a common uniting factor. They are made to undergo a treatment and then compared to those who did not receive the treatment. This type of study  is subject to bias because a positive or negative result might be because of other factors not related to the study.

What is the measure of angle A?

Answers

Answer:

A = 19.47

Step-by-step explanation:

Since this is a right triangle, we can use trig functions

sin theta = opp / hypotenuse

sin A = 2/6

Take the inverse sin of each side

sin ^-1 ( sin A) = sin ^-1 (2/6)

A =19.47122063

To the nearest hundredth

A = 19.47

Which expression is equivalent to 2(3x − 1.75) − 3(1.5x − 2.5)?

Answers

Answer:

1.5x+4

Step-by-step explanation:

Step-by-step explanation:

Step 1:  Distribute

[tex]2(3x - 1.75) - 3(1.5x - 2.5)[/tex]

[tex](2 * 3x) + (2 * -1.75) + (-3 * 1.5x) + (-3 * -2.5)[/tex]

[tex](6x) + (-3.5) + (-4.5x) + (7.5)[/tex]

Step 2:  Combine like terms

[tex](6x - 4.5x) + (7.5 - 3.5)[/tex]

[tex]1.5x + 4[/tex]

Answer:  [tex]1.5x + 4[/tex]

Which expression is equivalent to m n + z?
n m + n
z + m z
m z + n
z + n m

Answers

Answer:

z + n m

Step-by-step explanation:

These expressions are equivalent because the commutative property of addition, which states that when adding two terms, the order doesn't matter.

If this answer is correct, please make me Brainliest!

Answer:

It's "c"

Step-by-step explanation:

i just did this on edge

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