Suppose Diana, an educational researcher at a local university, wants to test the impact of a new Spanish course that integrates cultural-immersion teaching techniques with standard teaching practices. She selects a simple random sample of 64 freshmen and divides them into 32 pairs, matched on IQ and high school GPA. She randomly selects one member of each pair to take the new course, while the other member in the pair takes the traditional course.

Next, Diana records the course grade, tallied on a scale from 0 to 4, for all sample members at the end of the semester, and she computes the difference in grades between the members in each matched pair by subtracting the traditional course grade from the new course grade. She wants to determine if the new Spanish course improves or weakens student performance. She runs a matched-pairs t-test to test the null hypothesis, H0:μ=0, against the alternative hypothesis, H1:μ≠0, where μ is the mean course grade difference for the student population.

The sample statistics for Diana's test are summarized in the table.

Variable description Sample mean Sample standard deviation Standard error estimate

traditional course grade x⎯⎯trad= 3.33496 strad=2.02198 SEtrad=0.33700
new course grade x⎯⎯new=3.45287 snew=2.11043 SEnew=0.35174
difference (new − traditional) x⎯⎯=0.11791 s=0.31452 SE=0.05242


Although Diana does not know the standard deviation of the underlying population of course grade differences, she assumes that the population is normally distributed because the sample data are symmetric, single-peaked, and contain no outliers.

Required:
Compute the t-statistic for Diana's matched-pairs t-test.

Answer:

hope it is helpfulto you

Answer:

Step-by-step explanation:

The answer is 546

Answer:

Area = 18

Step-by-step explanation:

Trapezoid formula is Area = (a + b) * h/2

Area = 5 + 7 * 3/2

Area  = 18

9514 1404 393

Answer:

  (b)  S = 15,210

Step-by-step explanation:

The common ratio is ...

  r = 1369/1521 ≈ 0.90

So, the sum is ...

  S = 1521/(1 -r) = 1521/0.10 = 15,210 . . . . . sum of the series

9514 1404 393

Answer:

  (b)  S = 15,210

Step-by-step explanation:

The common ratio is ...

  r = 1369/1521 ≈ 0.90

So, the sum is ...

  S = 1521/(1 -r) = 1521/0.10 = 15,210 . . . . . sum of the series

Answer:

81

Step-by-step explanation:

3*3=9

9*3=27

27*3=81

Answer:  90

Step-by-step explanation:

3 to the fourth power =  81

81 + 9 = 90

Answer:

80/39

Step-by-step explanation:

Answer:

24 minutes

Step-by-step explanation:

We use 1/a + 1/b = 1/c

where a and b are the individual times and c is the time together

1/40 + 1/60 = 1/c

Multiply each side by 120c

120c( 1/40 + 1/60 = 1/c)

3c + 2c = 120

5c = 120

Divide each side by 5

5c/5 = 120/5

c = 24

Answer: 24 minutes

Step-by-step explanation: To solve this kind of a problem which is called a work problem, it's important to understand the following idea.

Since Elam can wire a light in 40 minutes, we know that in 1 minute,

Elam can wire 1/40 of the light and in 2 minutes, Elam can wire 2/40 of it.

Therefore, in t hours, Elam can wire t/40 of the light.

The same applies for Michael, in t hours, he can wire t/60 of the light.

So to solve the problem, we use the following formula:

Part of job done by Elam + part of job done Michael = 1 job done

The part of the job done by Elam is t/40 and t/60 for Michael.

So we have t/40 + t/60 = 1.

Now multiply both sides by 120 to get 3t + 2t = 120

or 5t = 120 so t = 24.

So it takes 24 minutes if they work together.

Hi there!

[tex]\large\boxed{\text{System G.}}[/tex]

For a system to have an infinite number of solutions, both expressions must be equal. We can go through each system and determine this:

F:

x + 2 = y

4 = 2y - x

If we rearrange so that both are in the same format, we get:

x + 2 = y

x + 4 = 2y

These cannot be equal, so they do not have infinite solutions.

G:

2y + 6 = 4x

-3 = y - 2x

Rearrange:

2y + 6 = 4x

-y - 3 = -2x

We can try to make the bottom equation look like the top equation by multiplying all terms by -2. We get:

2y + 6 = 4x. This is the same as the top, so G has infinite solutions.

Just to be sure, we can go through the others:

H:

y + 3 = 2x

4x = 2y - 3

Rearrange:

y + 3 = 2x

2y - 3 = 4x. Cannot be equal to the other equation.

J:

y = 2x - 5

y = 2x - 2. Not equal.

The correct answer is G.

In other words, only choice A and choice D are false.

====================================================

Explanation:

An included angle is one between two given sides. Think of the angle sandwiched in between.

For choice A, the included angle is actually angle R. This is because the "R" shows up in QR and RP. This is the overlapping or shared letter between the segments. So we can see that statement A is false.

In contrast, choice B and choice C are true. Choice B is true because of what I mentioned in the previous paragraph. Choice C is true because Q shows up in both QR and PQ. It might help to draw out the diagram to see why this works.

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

For choices D through F, we'll just take this logic in reverse.

The segment RP has angles R and P involved. In other words, segment RP is between angles R and P. We can rule out choice D since choice E is true.

Choice F is true as well because segment QP involves angles Q and P. No diagrams are needed but it might help to draw out the diagram to see what's going on.

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

Overall, we have four true statements and they are choices B, C, E and F.

Answer:

g(t) = 0; solve for t

Step-by-step explanation:

Given

Options (a) to (e)

Required

Which of the options is true

From the question, we understand that: g(t) represents hare's time to complete the race

At the beginning of the race, the time left to complete the race is at g(t) = 0; then solve for t.

Take for instance:

[tex]g(t) = 10 - t[/tex]

The time to complete the race is: g(t) = 0

So, we have:

[tex]0 = 10 - t[/tex]

Collect like terms

[tex]t = 10[/tex]

To determine the number of seconds that the hare would finish the race, we solve g(t) = 0, to calculate the value of t.

Linear equation is in the form:

y = mx + b

where y, x are variables, m is the slope of the equation (rate of change) and b is the y intercept (initial value of b).

Given that g (t) represents the hare's distance from the finish line (in meters) t seconds after the start of the race.

To determine the number of seconds that the hare would finish the race, we solve g(t) = 0, to calculate the value of t.

Find out more on Linear equation at: https://brainly.com/question/13763238

Answer:

yes

Step-by-step explanation:

3.24538 is rational

Answer:

(5,38)

Step-by-step explanation:

Use graphing calculator and the answer should be the point where the line crosses each other.

Answer:

5,38

Step-by-step explanation:

its correct!

Answer:

The answer is D

Hope this helps!

Brainliest??

Answer:

D

Step-by-step explanation:

the answer is D because if she already made 7 she need to add n to 7 to get 40 or greater

Answer:

the answer is b

Step-by-step explanation:

Answer:

b: 78.5cm²

Step-by-step explanation:

answer is b my friend

Answer:

n = 20

Step-by-step explanation:

[tex]\frac{16}{40} = \frac{8}{n}[/tex]

Cross multiplication would result in:

16 * n = 8 * 40

16n = 320

n = 320 / 16

n = 20

Therefore the value of "n" in this proportion is 20.

Hope this helps!

Answer:

[tex]14 \ 100 \1800[/tex]

Answer:

Step-by-step explanation:

Answer:

8/5

Step-by-step explanation:

First find h(-3)

 h(-3)= 4-(-3) = 4+3 = 7

Then take this result and find g(h(-3)) = g(7)

g(7) = (7+1)/( 7-2) = 8/5

2^( - 1 ) × 4^( -1 ) =

2^( -1 ) × 2^( 2 × ( - 1) ) =

2^( - 1 ) × 2^( - 2 ) =

2^( - 1 - 2 ) =

2^( - 3 ) =

1/ 2^( 3 ) =

1/8

Answer:

First three terms:

22,24,26

There are 15 terms in the sequence that are 50 or less, yet only 14 if its just less than 50.

Answers:

The first three terms are 21, 24, 29

5 terms of the sequence less than 50.

======================================================

Explanation:

Plug in n = 1 to find that n^2+20 = 1^2+20 = 1+20 = 21. The first term is 21.

Repeat for n = 2 and you should get 2^2+20 = 24 as the second term.

The third term is 29 through similar steps, but this time you use n = 3 of course.

The first three terms are 21, 24, 29

It's effectively the first three perfect squares 1, 4, 9 but we have a tens digit of 2 stuck to the left of each value.

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

We want to find when n^2+20 is less than 50. We could keep plugging values of n into that expression and record if the result is less than 50 or not, then tally those occurrences. You should record 5 such occurrences.

Or we could do a bit of algebra like so

n^2+20 < 50

n^2 < 50-20

n^2 < 30

sqrt(n^2) < sqrt(30)

n < sqrt(30)

On a calculator, sqrt(30) is roughly 5.4772 which means n < 5.4772. If n is a a natural number, then the largest it can get is n = 5 to ensure n^2+20 is less than 50.

We can see that,

This helps show that n = 5 is the largest n to make n^2+20 < 50 a true statement. This means that there are 5 terms of the sequence less than 50.

Answer:

x < 7

Step-by-step explanation:

-8x + 40> -16

Subtract 40 from each side

-8x + 40-40> -16-40

-8x >-56

Divide each side by -8, remembering to flip the inequality

-8x/-8 < -56/-8

x < 7

Answer:

0.05

Step-by-step explanation:

Because 1/5 divided by 4 gives you 0.05 or 1/20

Answer:

the answer is

This question is incomplete, the complete question is;

Your company is planning to air a number of television commercials during a television network's presentation of the an awards show. The network is charging your company $1.9 million per 30-second spot. Additional fixed costs (development and personnel costs) amount to $500,000, and the network has agreed to provide a discount of $160,000√x for x television spots.  

Required:

Write down the cost function C, marginal cost function C’, and average cost function

Answer:

- The  the cost function is 500,000 + 1,900,000x - 160,000√x

- the marginal cost function is 1,900,000 - (80000 /√x  )

- The  average cost function is 1,900,000 + [ 500,000 / x ] - [ 160,000 / √x ]

Step-by-step explanation:

Given the data in the question;

cost per spot = $1.9 million

Additional cost =  $500,000

discount = $160,000√x

 Let C(x) represent the cost ;

Cost x television spot = cost per spot × Number pf spots

Cost x television spot = $1.9 million × x

Cost x television spot = $1,900,000x

Now, the television set total cost will be;

C(x) = television cost + additional cost - discount  

C(x) = 500,000 + 1,900,000x - 160,000√x

Therefore, The  the cost function is 500,000 + 1,900,000x - 160,000√x

Marginal Cost Function;

Cost function C(x) = 500,000 + 1,900,000x - 160,000√x

we differentiate with respect to x

C'(x) = d/dx( 500,000 + 1,900,000x - 160,000√x )

= d/dx( 500000 ) + 1,900,000d/dx -160,000 d/d( √x )

= 0+ 1,900,000(1) -160,000( 1 / 2√x )

= 1,900,000 - (160,000 / 2√x  )

= 1,900,000 - (80000 /√x  )

Therefore, the marginal cost function is 1,900,000 - (80000 /√x  )

Average cost function;

Average cost function = C(x) / x

we substitute

Average cost function = [500,000 + 1,900,000x - 160,000√x] / x

=  [500,000 / x ] + [1,900,000x / x ]  - [ 160,000√x / x ]

=  [ 500,000 / x ] + 1,900,000 - [ 160,000√x / x ]

=  1,900,000 + [ 500,000 / x ] - [ 160,000 / √x ]

Therefore, The average cost function is 1,900,000 + [ 500,000 / x ] - [ 160,000 / √x ]

Answer:

the correct answer is A. Rhombus

The answer is D (Square)

Because the sides of a square are equal.

Answer:

Total number of days in the mines = 4.5 days  + 3 days ≥ 7.5 days

Step-by-step explanation:

Requirement : 12 Ibs gold and 18 Ibs silver  to pay monthly rent

Mine 1 ; 2 Ibs of gold , 2Ibs of silver.

Mine 2; 1 Ib of gold , 3 Ibs of silver

using LP

Gold :  aX1  + bX2 ≥  12   ---------- ( 1 )

Silver:  cX1  + dX2 ≥  18  --------- ( 2 )

where; X1 = days spent in Mine 1

            X2 = days spent in Mine 2

Total days spent in mines : X1 + X2 =

a = Gold found in mine 1  = 2

b = Gold found in mine 2 = 1

c = silver found in mine 1 = 2

d = silver found in mine 2  = 3

Back to equations 1 and 2

2X1 +  X2   ≥  12 ----------- ( 3 )

2X1 + 3X2  ≥  18  ------------ ( 4 )

solving equations 3 and 4

= 0 +  2X2 ≥ 6  ∴ X2 ≥ 3 days  ( days spent in mine 2 )

Input value into ( 3)

2X1 ≥ 12 - 3 = 9

∴ X1 ≥ 4.5 days ( days spent in mine 1 )

Total number of days in the mines = 4.5 days  + 3 days ≥ 7.5 days

================================================

Explanation:

I'll be using the formula

[tex]_n C _r = \frac{n!}{r!*(n-r)!}[/tex]

which is the nCr combination formula. We use nCr instead of nPr because the order of coasters doesn't matter. The whole time, the value of n stays fixed at n = 17 which is the total number of coasters to pick from.

While n is constant, the value of r will vary. It ranges from r = 15 to r = 17 inclusive of both endpoints. In other words, r will take on values from the set {15,16,17}. So we have three cases to consider. The r value is how many coasters we select. This is due to the "at least 15" which means "15 or more".

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

If you ride r = 15 coasters, then we have the following number of combinations

[tex]_n C _r = \frac{n!}{r!*(n-r)!}\\\\_{17} C _{15} = \frac{17!}{15!*(17-15)!}\\\\_{17} C _{15} = \frac{17!}{15!*2!}\\\\_{17} C _{15} = \frac{17*16*15!}{15!*2!}\\\\_{17} C _{15} = \frac{17*16}{2!}\\\\_{17} C _{15} = \frac{17*16}{2*1}\\\\_{17} C _{15} = \frac{272}{2}\\\\_{17} C _{15} = 136\\\\[/tex]

There are 136 ways to ride exactly 15 coasters (when selecting from a pool of 17 total). The order doesn't matter.

We'll use this result later, so let x = 136.

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

If r = 16, then we follow the same steps as above. You should get 17C16 = 17

There are 17 ways to ride 16 coasters where order doesn't matter. Effectively this is the same as saying "there are 17 ways of picking a coaster that you won't ride"

Let y = 17 so we can use it later

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

Lastly, if r = 17, then nCr = 17C17 = 1 represents one way to ride all 17 coasters where order doesn't matter.

Let z = 1

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

Add up the values of x, y, and z to get the final answer

x+y+z = 136+17+1 = 154