A random sample of 100 chemistry students were asked how many lab classes he or she was enrolled in september 2000. the results showed a mean of 1.65 lab classes with a standard deviation of 1.39. ten years later, a similar survey was conducted to determine if the distribution changed. the 2010 sample mean was 1.82 with a standard deviation of 1.51. do the data provide statistical evidence that the mean number of lab classes taken in the first survey is different from the survey taken 10 years later? perform the appropriate test using a = 0.02​

Answers

Answer 1

Using the t-distribution, as we have the standard deviation for the samples, it is found that the data does not provide statistical evidence that there is a difference.

What are the hypotheses tested?

At the null hypotheses, it is tested if there is no difference in the means, that is, the subtraction is of 0, hence:

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

At the alternative hypotheses, it is tested if there is a difference, hence:

[tex]H_1: \mu_1 - \mu_2 \neq 0[/tex]

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

For each sample, they are given by:

[tex]\mu_1 = 1.82, s_1 = \frac{1.51}{\sqrt{100}} = 0.151[/tex]

[tex]\mu_2 = 1.65, s_2 = \frac{1.39}{\sqrt{100}} = 0.139[/tex]

Hence, for the distribution of differences, they are given by:

[tex]\overline{x} = \mu_1 - \mu_2 = 1.82 - 1.65 = 0.17[/tex]

[tex]s = \sqrt{s_1^2 + s_2^2} = \sqrt{0.151^2 + 0.139^2} = 0.205[/tex]

What is the test statistic?

The test statistic 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.

Then:

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

[tex]t = \frac{0.17 - 0}{0.205}[/tex]

[tex]t = 0.83[/tex]

What is the decision?

Considering that it is a two-tailed test, as we are testing if the mean is different of a value, with 100 + 100 - 2 = 198 df and a significance level of 0.02, the critical value is of [tex]|t^{\ast}| = 2.3453[/tex].

Since the absolute value of the test statistic is less than the critical value, we do not reject the null hypothesis, which means that the data does not provide statistical evidence that there is a difference.

More can be learned about the t-distribution at https://brainly.com/question/13873630


Related Questions

What is the pattern;
1=4
2=4
3=64
4= ?

Answers

Answer:

64

Step-by-step explanation:

because the next number is equal to the same

Answer:

256

Step-by-step explanation:

Look closely at the stated list in the question:

1=4

2=16

3=64

Notice that the second number is reached by taking the first number and placing it as an exponent to 4.

4^1=4

4^2=16

4^3=64

So the missing number must be 4^4 which is equal to 256

Donna bought 5 bags of dog treats for 12.55. What is the cost per bag

Answers

Answer:

$2.51

Step-by-step explanation:

12.55/5= 2.51

a bag of dog treats is 2.51 per bag

Which expression is a factored form of 2x2
25x + 63?

Answers

The expression of  the factored form of 2x2+25x + 63 is mathematically given as

(x+7)(2x+7)

What is the expression of  the factored form of 2x2+25x + 63?

Question Parameter(s):

Expression 2x^2+25x + 63?

The expression of the factored form will bear the roots of the expression repressented  in standard form

Generally, the equation for the expression   is mathematically given as

2x^2+25x + 63?

Therefore

2x^2+25x + 63?

x(2x+7)+9(2x+7)

(x+7)(2x+7)

In conclusion, The expression is

(x+7)(2x+7)

Read more about Arithmetic

https://brainly.com/question/22568180

The area of a square is (9a2 − 24a + 16) square units. determine the length of each side of the square by factoring the area expression completely. show your work.

Answers

The will be 3x+4 I hope this help you

32+4 X (16 X ) -2 show your work

Answers

Answer:

32+4x(16x)-12=

32+64x-12=

64x-12+32=64x+20

64×÷64÷=20÷64=

x=0.3125

what is your favirote subject

Answers

Answer:

My favorite subject is Science

Step-by-step explanation:

Because it’s really interesting and the concepts about everything that could and will happen is fascinating

I love math just because i love counting money & i love to read

Two angles in a triangle add up to 152 degrees.
what is the size of the third angle?

Answers

Answer:

28 degrees

Step-by-step explanation:

A triangle is 180 degrees. 180-152=28.

Answer:

The third angle is 28 degrees

Step-by-step explanation:

A triangle has to add up to 180 degrees so just take 180 subtract your 152 from it and you'll have your answer!. (180 - 152 = 28) Hope this helps! :)

What is the angle of rotation for point G mapped to point H?

90° clockwise
72° clockwise
72° counterclockwise
90° counterclockwise

Answers

The rotation of point G to point H is an illustration of a circular movement

The rotation that maps point G to point H is 72 degrees clockwise

How to determine the rotation rule?

From the figure, we have the following parameters:

Number of sections (n) = 5

Angle at the center = 360

The angle of rotation is then calculated as:

Rotation = 360/5

Evaluate

Rotation = 72

Point H is to the left of point G.

This represents a clockwise direction

Hence, the rotation that maps point G to point H is 72 degrees clockwise

Read more about rotation at:

https://brainly.com/question/4289712

Answer:

72° clockwise

Step-by-step explanation:

(PLS Need Help ASAP) Don't answer if you don't know pls.

Answers

Answer:

y = - x + - 2

Step-by-step explanation:

Using the equation y = mx + b, find the m (slope) from the graph and the b (y-intercept from the graph).  The slope, m, is the rise over the run from point A to point B.  The rise is -5 and the run is 5.  [tex]\frac{-5}{5}[/tex] = -1.  The y-intercept, b, is the point the graph passes through the y-axis.  The b is -2 so y = -x+-2.

Answer:
y=-x+-2

Step-by-step explanation:
Slope Intercept Form= Y=mX+b
with b as the slope and b as the y-intercept
also the graph has a negative slope

the slope is -x
the y-intercept is -2

Find the value of each variable. 22, 30, x.
x=
y=
(Simplify your answers. Type exact answers, using radicals as needed. ​
please hurry for fifty points!

Answers

Answer:

11 and 11 root 3

This is because it is a 30 60 90 triangle, making it x, x root 3, and 2x.

Answer:

x = 11, y = 19.05

Step-by-step explanation:

sin 30 = x/22
22*sin 30 = x

22*0.5 = x
11 = x

tan 30 = 11/y
0.577350269 = 11/y
y = 11/0.577350269
y = 19.0525589
y= 19.05

Hope this helps :)

Please help I'm extremely confused.

Find the value of x. Round to the nearest tenth. The diagram is not drawn to scale. (picture of diagram included )​

Answers

Answer:

8.4 is the correct answer on acellus

PLS HELP ASAP PLSSS PLSSS FIRST CORRECT ANSWER GETS BRAINLIEST PLS ANSWER​

Answers

Answer:

sqrt(37) = arpox 6.1

Step-by-step explanation:

sqrt(1^2+6^2) = sqrt(37)

learn.flvs.net/educator/student/examform.cgi?eprice34 annсait*sit=bNTabyUk8FP9A*4870*0017
Lessons
W FLVS
Assessments
✓ Gradebook
Email 9
$ Tools -
Question 4(Multiple Choice Worth 1 points)
(03.01 MC)
Simplify 972-317 + V8 - 28
011/2-5/7
0 1184 – 5/14
065
be
C 6/9
Question 5 Multiple Choice Worth 1 points)
(03.01 LC

Answers

Answer:

The choice A.

Step-by-step explanation:

[tex]9 \sqrt{2} - 3 \sqrt{7} + \sqrt{8} - \sqrt{28} \\ \\ 9 \sqrt{2} - 3 \sqrt{7} + ( \sqrt{2} \sqrt{4} ) - ( \sqrt{4} \sqrt{7} ) \\ 9 \sqrt{2} - 3 \sqrt{7} + (2 \sqrt{2} ) - (2 \sqrt{7} ) \\ 9 \sqrt{2} - 3 \sqrt{7} + 2 \sqrt{2} - 2 \sqrt{7} \\ (9 \sqrt{2} + 2 \sqrt{2} ) + ( - 3 \sqrt{7} - 2 \sqrt{7} ) \\ 11 \sqrt{2} - 5 \sqrt{7} [/tex]

The simplified value of in radical form is 11√2 - 5√7.

What is Radical?

In mathematics, a radical is the inverse of an exponent, which is represented by the symbol '√' , also known as root. It can be a square root or a cube root, and the number preceding the symbol or radical is known as an index number or degree. This is a whole integer with an exponent that cancels out the radical.

We have 9√2 - 3√7 + √8 - √28

First, solve the radical as possible

√8= 2√2

and, √28= 2√7

So, 9√2 - 3√7 + √8 - √28

= 9√2 - 3√7 + 2√2- 2√7

= 9√2 + 2√2- 3√7- 2√7

= 11√2 - 5√7

Learn more about Radical here:

https://brainly.com/question/1369233

#SPJ7

A bike rental company charges its customers p dollars per day to rent a bike, where 5≤p≤30. the number of bikes rented per day can be modeled by the linear function n(p)=300−10p. how much should the company charge each customer per day to maximize revenue? do not include units or a dollar sign in your answer.

Answers

Using the vertex of a quadratic equation, it is found that the company should charge each customer $15 per day to maximize revenue.

What is the vertex of a quadratic equation?

A quadratic equation is modeled by:

[tex]y = ax^2 + bx + c[/tex]

The vertex is given by:

[tex](x_v, y_v)[/tex]

In which:

[tex]x_v = -\frac{b}{2a}[/tex][tex]y_v = -\frac{b^2 - 4ac}{4a}[/tex]

Considering the coefficient a, we have that:

If a < 0, the vertex is a maximum point.If a > 0, the vertex is a minimum point.

In this problem, the number of bikes rented per day is given by:

n(p) = 300 - 10p.

Hence, the revenue function is given by:

R(n) = p x n(p)

R(n) = 300p - 10p².

Which is a quadratic function with coefficients a = -10, b = 300. Hence, the price in dollars that will maximize the revenue is given by:

[tex]x_v = -\frac{300}{-20} = 15[/tex]

More can be learned about the vertex of a quadratic equation at https://brainly.com/question/24737967

this is due tomorrow at 8 pls help

Answers

Answer:

a = 4 b = 2 c = 6

Step-by-step explanation:

4 + b = c

b & c are any even numbers between 2 and 9 (2, 4, 6, 8)

c > 4 ( 6, 8)

b < 6 (2, 4)

b can't be the same number, so b is 4 meaning c is 6

Answer:

b=2, c=6

Step-by-step explanation:

9 markers cost $7. 50. How much would 7 markers cost

Answers

Answer:

5.83

Step-by-step explanation:

9 / 7.50 = 0.833(repeating)

8.33(repeating) * 7 = 5.833(repeating)

Simplify 5.833(repeating)

Answer:

5.83

Step-by-step explanation:

Which choice shows (9 x 3) x 20 correctly rewritten using the associative property and then correctly simplified?

Answers

Answer:

I'm guessing it is 3x(9x20)=3x180=540

Step-by-step explanation:

IDENTIFY THE PROPERTY WHICH JUSTIFIES THE FOLLOWING CONCLUSION

A. REFLECTIVE PROPERTY
B. ADDITION PROPERTY OF EQUALITY
C. SYMMETRIC PROPERTY
D. MULTIPLICATION PROPERTY OF EQUALITY

1. If ×=4, then × + 2=7
....__.....__
2.AB = AB

3. If × = y, Then 2× = 2y

4. If 9 = 6+3, then 6+3 =9

Please answer correctly do not concentrate wrong and rely only on the pontos:)​

Answers

Answer:

Step-by-step explanation:

17) B. They are adding 2 to both sides.

18) A. A segment is equal to itself.

19) D. They are multiplying both sides by 2.

20) C. They are simply swapping the left and right hand sides of the equation

PLEASE ANSWER QUICKLY!!! Find the area of the following shape

Answers

Answer:

  30 cm²

Step-by-step explanation:

You want to know the area of the given shape.

Parallelogram

The formula for the area of a parallelogram is ...

  A = bh

A line from B to E divides the figure into two congruent parallelograms, each having a base of 5 cm and a height of 3 cm.

The area of the figure is ...

  A = 2 × (5 cm)(3 cm) = 30 cm²

__

Additional comment

If you draw a line from F to D you get a triangle FED that perfectly matches the space ABC. Moving ∆FED to fill ∆ABC transforms the figure into a rectangle that is 5 cm high and 6 cm wide. Its area is (5 cm)(6 cm) = 30 cm².

<95141404393>

What is X?
(x+22) 2x
(Need help)

Answers

Answer:

nasa pic yung sagot

hope its help

can someone please help me

Answers

40 dollars is the setup so it happens only once. It is a fixed cost.
10 dollars is for each shirt so it is a variable cost. Happens for every shirt.

Y is total cost:

Y= 40 + 10x

For one shirt:
Y=40+10(1)
Y=50

For five shirts:
Y=40+10(5)
Y= 90

For ten shirts:
Y=40+10(10)
Y=140

For fifty shirts:
Y=40+10(50)
Y= 540



Hello people ~
factorise↷
x^2 + 4x –21​

Answers

Let's see

[tex]\\ \rm\rightarrowtail x^2+4x-21[/tex]

[tex]\\ \rm\rightarrowtail x^2+7x-3x-21[/tex]

[tex]\\ \rm\rightarrowtail x(x+7)-3(x+7)[/tex]

[tex]\\ \rm\rightarrowtail (x-3)(x+7)[/tex]

Martin drew a scale drawing of an arcade. The scale he used was 1 inch : 3 feet. If the actual length of an air hockey table is 9 feet, how long is the air hockey table in the drawing?

Answers

Answer: 3 inches

Step-by-step explanation: 9 divided by 3 is 3

If it is now two o'clock, how many hours later will be the first hour between the arrows of the clock is 90 degrees

Answers

Answer: 4 o clock

Step-by-step explanation:

Answer:

5 o' clock

Step-by-step explanation:

The angle between the hands of a clock on an hourly basis is 30°

thus for the hands to be 90° apart would be 3 hours

then 2 o' clock + 3 hours = 5 o' clock

The photo is shown below, please help!

Answers

Answer/Explanation:

The formula for a rectangular prism is Length x Width x Height

With this information we can multiply 6x8x2 and get 96 ft³.

This is the volume of the original prism.

Doubling the dimensions means multiplying each side by 2.

The new dimensions would be a.16 b.4 c.12

Use the formula to find volume. 12x16x4=768

The volume of the enlarged prism is 768 feet³

For bonus question, divide 768 by 96.

The scale factor is 8.

What time would it be if the minute hand rotated by 180 degrees from the current time?

2:30
4:00
3:30
2:15

Answers

Answer:

3:30 is the answer

if 192 students are in 4 buses how many students are in each bus?

Answers

Answer:

48

Step-by-step explanation:

192/4=48

Hope this helps!!!

Answer:

48 students

Step-by-step explanation:

Given that:

192 student are in 4 buses

To Find:

How many students are in each bus

Solution:
To find how many students are in each bus we have to divide. 192 by 4.

192 ÷ 4  which given us 48.

Therefore, there are 48 students in each bus.

~lenvy~

thankyou for all the help

Answers

Answer:

1. x + y = 180

2. x = 50 y= 130

Step-by-step explanation:

They're parallel.

We can label the unamed angle z.

So z = y

and 50 = x

There's 360 degrees in a circle, so x + y= 180 because it's half 360 and half a circle.

x=50

so 50 + 50 = 100.

360 - 100 = 260

so 260 ÷ 2 = 130

y = 130 because y and z are equal so they're the same number

Step-by-step explanation:

1. x+y=180

hope that helps

A salesperson earned x dollars last year. The salesperson earned 25% more money this year than last
year. Which expressions represent the amount, in dollars, the salesperson earned this year?
Drag and drop each correct expression into the box.
HELP PLS

Answers

Earnings last year=xMore earnings percentage=25%

More earnings:-

25% of x0.25x

Total earnings this year

x+0.25x(1+0.25)x$1.25x

Answer:

[tex]\$ \huge{\text{(} \dfrac{x}{4} \ + \ \dfrac{4x}{4} \huge{\text{)}[/tex]

Step-by-step explanation:

Given:

Last year: $x

Determining the money earned for this year:

This year = 25%   more than       last year

               = $25x/100   +                    $x

               = $x/4           +                 $4x/4

The expression that represents the money earned this year is $x/4 + $4x/4.

WHOEVER RESPONDS FIRST WILL GET MARKED BEST.
A circle has a diameter of 14.5 inches. Using 3.14 for 1, what is the circumference of the circles, rounded to the nearest hundredth of an inch?
22.77 inches
45.53 inches
91.06 inches 165.05 inches

Answers

[tex]c = 2 \pi \: r[/tex]

[tex]c = 2 \times 3.14 \times 14.5[/tex]

[tex]c = 91.06[/tex]

Answer:

2nd option - 45.53 inches

Step-by-step explanation:

Circumference of a circle when given the diameter is given by the formula :

[tex]\pi d[/tex]

Since we are given a certain value for pi we use that and multiply it by the diameter to given the cirumference:

3.14 × 14.5 in  =

45.53 inches

Therefore our answer is 43.53 inches (the 2nd option)

Other Questions
Which of the following types of organisms use ATGC bases in their DNA?A)BacteriaB)PlantsC)AnimalsD)All of the above Can anyone solve this correctly? Where does photosynthesis take place?in the stem of a plantin the roots of a plantin the chloroplasts of a leafin the stomata of a leaf While walking in the woods, which poet "took the road less traveled by?". How much money will you have in 6 months if you invest $1000 at 3% compounded monthly?AnswersStep-by-step explanation Observations of the center of the Milky Way show the presence of a super massive black hole with a mass of 4.6 x 106 solar masses. Compute the Schwarzschild radius of this supermassive black hole. Give your answer in units of astronomical units (AU). At what distance does Mercury orbit from the Sun in AU? If we swapped out the Sun for this super massive black hole, would the event horizon extend beyond the orbit of Mercury? Be sure to show your calculations. 1 AU = 1.5 x 108 km. pls help ! MAPPING SHAPESA) only sequence a b) only sequence b c)bothd) neither Use the calculator to find the product. (1. 466 108)(5. 02 105) What is the coefficient of the product? What is the exponent of the power in the product?. What are the possible transformations that could have been used to create the red figure from the blue figure ABCD? 1. liola drives 130 m up a hill that has a slope of 7. what horizontal distance, to the nearest hundredth of ameter, has she covered?o 129. 03 mo 15. 84 mo 15. 96 mo 130. 97 m The area of the triangle is 22.4 cm2. Calculate the length, b, of the longest side of the triangle. 97 3.7 cm a b t divided by 5 = 2.9What step should be performed on both sides of this equation to find the solution?Add 5.Subtract 5.Multiply by 5.Divide by 5. After years of false starts in disappointing career paths, bruce feels happy. More than that, he feels that he is living up to his potential and doing what he is meant to do with his life. What state has bruce reached?. Why is Alfred Marshall important to the study of economics? Read the excerpt from "a worn path." 'phoenix spoke unasked now. "no, missy, he not dead, he just the same. every little while his throat begin to close up again, and he not able to swallow. he not get his breath. he not able to help himself. so the time come around, and i go on another trip for the soothing-medicine." "all right. the doctor said as long as you came to get it, you could have it," said the nurse. "but it's an obstinate case."' what is the most likely the meaning of obstinate? The experimental probability of a quarter landing on HEADS is 3/5 if the quarter landed on TAILS 36 times how many times tossed. how does the body use vitamins and minerals High-efficiency particulate air (HEPA) filters are designed to remove which sized particles from the environment? 0.1 microns or smaller a) b) 0.3 microns or larger O c) 0.1 microns or larger d) 0.3 microns or smaller Write an equation for the graph in terms for xY= Read the passage to answer the question that follows. The little people carried Gulliver to the city by _____. a horse a cart with twenty-two wheels a carriage