In testing the difference between two population means using two independent samples, the sampling distribution of the sample mean difference x?1 ? x?2 is normal if the
A. populations are normal.
B. population sizes are both greater than 30.
C. populations are nonnormal and the sample sizes are large.
D. sizes are both greater than 30.

Answers

Answer 1

Answer:

C. populations are non normal and the sample sizes are large.

Step-by-step explanation:

To test hypotheses about the difference between two populations means we deal with the following three cases.

1) both the populations are normal with known standard deviations.

2)both the populations are normal with unknown standard deviations.

3) both the populations are non normal in which case both the  sample sizes are necessarily large.

So option C is the correct answer.


Related Questions

Two bags contain 10 balls each. Every round, you choose with equal probability one of the 2 bags and pick out a ball. After a while, you choose an empty bag. What is the probability for the other bag to contain exactly 4 balls at that time?
a. 2.90%
b. 6.10%
c. 10.80%
d. 12.20%

Answers

Answer: b) 6.10%

Step-by-step explanation:

to find the probability for the other bag to contain exactly 4 balls at that time;  

is only possible if you have chosen a particular bag 10 times and other bag 6 times.

After that, once again at the 17th attempt

so the required probability =     ¹⁶c₁₀ × (1/2¹⁰ × (1/2)⁶ × (1/2)

= 0.610

CONVERT TO PERCENT

0.610 × 100

= 6.10%

Help! ASAP pls There is a frog dead in the center of the pond on a lily pad. The pond is 7 meters in diameter. There are 6 lily pads leading to the edge, which the frog MUST jump onto if he wishes to get out. The frog can only jump to 3 pads each day. How many days will it take him to get to the edge of the pond? And give an explanation

Answers

Answer:

Approximately 2 days.

Step-by-step explanation:

The frog can only jump 3 lily pads each day.

24 hours = 1 day

[tex]\frac{24}{3}[/tex] = 8 hours

Thus, it would take the frog 8 hours to cover a lily pad.

To get to the edge of the pond, the frog would jump through 6.5 lily pads (since he is at the middle of a lily pad at the center of the pond).

So that;

Total time required to get to the edge of the pond can be determined by;

6.5 × 8 hours = 52 hours

Number of days to get to the edge of the pond = [tex]\frac{52}{24}[/tex]

                                                                    = 2.2

It would take him approximately 2 days to get to the edge of the pond.

What's the value of x in the figure? A) 78° B) 57° C) 76° D) 33°

Answers

Answer:

x = 78

Step-by-step explanation:

57° + x° = 135° (alternate angles, // lines)

x = 135 - 57

= 78

I hope this helps :)

A unit vector lies in the xy plane, at an angle of 137 degrees from the x axis, with a positive y component. What is the unit vector

Answers

Answer: ( -0.731,  0.682)

Step-by-step explanation:

The unit vector is defined as a vector that points in the same direction as our vector (137 degrees from the x-axis) and has a magnitude of 1.

Knowing the angle, is really simple to do it.

First, we know that for a radius R and an angle A, the rectangular coordinates can be written as:

x = R*cos(A)

y = R*sin(A)

And if we want that the magnitude/modulus of our vector to be 1, then R = 1, and we know that A = 137°

x = 1*cos(137°) = -0.731

y = 1*sin(137°) = 0.682

Then the unit vector is: ( -0.731,  0.682)

The unit vector is ( -0.731,  0.682)

The calculation is as follows:

[tex]x = R\times cos(A)\\\\y = R\times sin(A)[/tex]

And the magnitude/modulus of our vector to be 1, then R = 1, and we know that A = 137°

so,  

[tex]x = 1\times cos(137) = -0.731y = 1\times sin(137) = 0.682[/tex]

Then the unit vector is: ( -0.731,  0.682)

learn more: https://brainly.com/question/20492533?referrer=searchResults

3-7 Please Help BRAINLEST

Answers

Hi there! Hopefully this helps!

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

Answer: r = 7.~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~

[tex]17 = r + 10[/tex]

Swap sides so that all variable terms are on the left hand side.

[tex]r + 10 = 17[/tex]

Subtract 10 from both sides.

[tex]r = 17 - 10[/tex]

Subtract 10 from 17 to get, you guessed it, 7!
Answer : r = 7
Using transposition method taking 10 to LHS will be -10
= r = 17-10
r = 7
Verification :
17 = r + 10
17 = 7+10
17 = 17
HENCE, LHS=RHS

(a) The perimeter of a rectangular field is 310 m.
If the length of the field is 84 m, what is its width?

(b) The area of a rectangular painting is 5185 cm.
If the width of the painting is 61 cm, what is its length?

Answers

Answer:

a. [tex] \boxed{ \bold{ \boxed{ \sf{width \: of \: rectangular \: field \: = 71 \: meter}}}}[/tex]

b. [tex] \boxed{ \bold{ \boxed{ \sf{length \: of \: rectangular \: painting \: = 85 \: cm}}}}[/tex]

Step-by-step explanation:

a. Given,

Perimeter of rectangular field ( P ) = 310 m

Length of the field ( L ) = 84 m

Width of the field ( W ) = ?

Finding the width of the rectangular field

[tex] \boxed{ \sf{perimeter \: of \: rectangle = 2(l + w)}}[/tex]

plug the values

⇒[tex] \sf{310 = 2(84 + w)}[/tex]

Distribute 2 through the parentheses

⇒[tex] \sf{310 = 168 + 2w}[/tex]

Swap the sides of the equation

⇒[tex] \sf{168 + 2w = 310}[/tex]

Move 168 to right hand side and change it's sign

⇒[tex] \sf{2w = 310 - 168}[/tex]

Subtract 168 from 310

⇒[tex] \sf{2w = 142}[/tex]

Divide both sides of the equation by 2

⇒[tex] \sf{ \frac{2w}{2} = \frac{142}{2} }[/tex]

Calculate

⇒[tex] \sf{w = 71 \: m}[/tex]

Width = 71 meters

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

2. Given,

Area of rectangular painting ( A ) = 5185 cm²

Width of the painting ( w ) = 61 cm

Length of the painting ( l ) = ?

Finding length of the painting

[tex] \boxed{ \sf{area \: of \: rectangle = l \times w}}[/tex]

plug the values

⇒[tex] \sf{5185 = 61l}[/tex]

Swap the sides of the equation

⇒[tex] \sf{61 \: l \: = 5185}[/tex]

Divide both sides of the equation by 61

⇒[tex] \sf{ \frac{61 \: l}{61} = \frac{5185}{61} }[/tex]

Calculate

⇒[tex] \sf{l = 85}[/tex] cm

Length = 85 cm

Hope I helped!

Best regards !!!

Please help me! i need to do this by Friday

Answers

Answer:

Step-by-step explanation:

x+118 degrees =180 degrees

x +118 degrees-118degrees =180 degrees - 118 degrees

                                         x =62 degrees

Question: -2 - (-4)

Answers

Answer:

2

Step-by-step explanation:

Follow PEDMAS

[tex]-2 - (-4)[/tex]

Follow rule : -(-a)= + a

[tex] - 2 + 4 \\ = 2[/tex]

Answer:2

Step-by-step explanation:

How much is 18% Equal to in a decimal

Answers

Answer: .18

Step-by-step explanation:

Ivan and Adeline are in a classroom with a chalkboard. They are standing on different halves of the board, and on each half, the number $2$ is written. When Ivan's teacher gives a signal, Ivan multiplies the number on his side of the board by $-2$ and writes the answer on the board, erasing the number he started with. Adeline does the same on each signal, except that she multiplies by $2$. The teacher gives 10 signals in total. How many times (including the initial number) do Ivan and Adeline have the same number written on the board (including at the beginning)?

Answers

Answer:

The number of times Ivan and Adeline have the same number written on the board is 6.

Step-by-step explanation:

Consider the procedure as follows:

On each half of the board, the number 2 is written.On Ivan's teacher's signal, Ivan multiplies the number on his side of the board by -2 and writes the answer on the board, erasing the number he started with.Adeline does the same on each signal, except that she multiplies by 2. The teacher gives 10 signals in total.

Consider the numbers on each half of the board:

          Ivan                            Adeline

             2                                     2

      2 × -2 = -4                        2 × 2 = 4

     -4 × -2 = 8                         4 × 2 = 8

      8 × -2 = -16                      8 × 2 = 16

   -16 × -2 = 32                      16 × 2 = 32

   32 × -2 = -64                    32 × 2 = 64

  -64 × -2 = 128                   64 × 2 = 128

  128 × -2 = -256               128 × 2 = 256

-256 × -2 = 512                256 × 2 = 512

  512 × -2 = -1024              512 × 2 = 1024

-1024 × -2 = 2048           1024 × 2 = 2048

Thus, the number of times Ivan and Adeline have the same number written on the board is 6.

HELP ME WITH THIS PROBLEM PLEASE the problems are 1-3
(The problems are in a picture)

Answers

1. 3 times a number less than the sum of twice a number and 2.

Let x be the number

The sum of twice of x and 2 is 2x + 2.

3 times a number less than this is 2x + 2 - 3x = -x + 2.

2. 6 multiplied by the sum of a number and 8.

Let x be the number

The sum of a number and 8 is x + 8.

6 multiplied by this is 6(x+8) = 6x + 48

3. Jane saves $10 per week, so after w weeks, she saves 10w.

She already has $50, so she then has 50 + 10w.

Compute the (sample) variance and standard deviation of the data sample. (Round your answers to two decimal places.) −8, 2, 2, 4, 15 variance standard deviation

Answers

Answer:

Variance = 67.00Standard deviation ≈ 8.19

Step-by-step explanation:

Before we can calculate the standard deviation of the dataset, we need to get the mean value first.

mean = sum of the values/total number given

mean = -8+2+2+4+15/5

mean = 15/5

mean (xbar) = 3

For ungrouped data:

Variance S²=  ∑(xi-xbar)²/N-1

xi are the individual values

xbar is the mean value = 3

N is the total number in the dataset = 5

Variance = (-8-3)²+(2-3)²+(2-3)²+(4-3)²+(15-3)²/5-1

S² = (-11)²+(-1)²+(-1)²+(1)²+(12)²/4

S² = (121+1+1+1+144)/4

S² = 67

Hence the variance of data sample is 67.00

Standard deviation is the square root of the variance.

√S² = Standard deviation

√67 = Standard deviation

Standard deviation = 8.185

Standard deviation ≈ 8.19 (to 2 decimal place)

Which shows the numbers One-tenth, 0.9, Three-tenths in order from least to greatest?

Answers

Answer:

Hello! Answer below! :)

Step-by-step explanation:

**Least to greatest** => [tex]1/10 < 3/10 < 0.9[/tex]

Look at the picture below!

By: RobloxYt

If _____, the Triangle)ABC and Triangle)EFD are congruent by the ASA criterion
-Angle B is congruent to angle E
-Angle C is congruent to angle E
-Angle a is congruent to angle E

If______,then triangle)ABC and triangle)EFD are congruent by the SES criterion
-AB = DE
-BC = FD
-CA = FD

Answers

Answer:

1). Angle c is congruent to angle E

2) BC=FD

Let a function f (x) = x² + 1
Find f (4):​

Answers

Answer:17

Step-by-step explanation:

Plug in 4 in the place of x and then add 1

[tex] &#128075 [/tex] Hello ! ☺️

Step-by-step explanation:

F(x)= x² +1

[tex] f(4) = 4 {}^{2} + 1 [/tex]

[tex] f(4)= 16+1 [/tex]

[tex]\boxed{\color{gold}{f(4) = 17}} [/tex]

[tex]<marquee direction="left" scrollamount="2" height="100" width="150">&#x1F498;Mynea04</marquee>[/tex]

what is forty nine eight hundred and one ten thousands in a decimal​

Answers

Answer:

forty nine eight hundred in a decimal

= 49800.0

one ten thousands in a decimal​

= 10000.00

Step-by-step explanation:

forty nine eight hundred and one ten thousands in a decimal​

First of all.

Let's take forty nine eight hundred

Converting it to decimal

= 49800.0

forty nine eight hundred= 49800.0

For the second one

one ten thousands in a decimal​

Converting it to decimal

= 10000.00

one ten thousands in a decimal​

= 10000.00 in decimal

Find ordered pair that is solution for liner equation 4x - 5y=20

Answers

Answer:

(0,-4) (5,0)

Step-by-step explanation:

4x-5y=20

First, we must put the equation into slope intercept form: y= mx+b

5y=4x-20=y=4/5x-4

The y intercept, by definition, is b. In this scenario, b is -4.

One ordered pair that works is (0,-4).

Also, we can find the ordered pair for the x intercept. By definition, the x intercept is the value of x when y equals zero. hence, we substitute 0 for y and then we can find an ordered pair that works and solve for x!:

0=4/5(x)-4= 4=4/5x4x=20x=5

Therefore, (5,0) works as well!

Evaluate the expression: 15c4
A. 8,190
B. 32,760
C. 1,365
D. 5,460

Answers

Answer:

C. 1365

Step-by-step explanation:

The expression nCr can be written with the simple equation:

n! / ((n-r)! * r!)

So to evaluate 15C4:

15! / ((15-4)! * 4!)

= 1365

So 15C4 = 1365

Cheers.

Answer:

1365

Step-by-step explanation:

15!/4!(15-4)!

1365

I need help with this question !!!!!!!

Answers

Answer:

f(x) = -5 if -5 <= x <= -3

f(x) = -2 if -3 < x <= 2

f(x) = 5 if 2 < x <= 6

Step-by-step explanation:

This is a simple piece wise function. Notice there are three lines or "solutions" for y-values over a range of x-values. Also notice there are filled in and not filled in circles. If the circle is not filled in, then it is not a solution. If it is, then it is a solution.

So for this, -5 is the solution if the range of x is from -5 through -3 inclusive since it has filled in circles.

-2 is a solution if the range of x is from -3 exclusive through 2 inclusive since at -3 it's open circle and 2 is filled.

5 is a solution if the range of x is from 2 exclusive through 6 inclusive since 2 it's open circle and 6 is filled.

To right that in notation simply

f(x) = -5 if -5 <= x <= -3

f(x) = -2 if -3 < x <= 2

f(x) = 5 if 2 < x <= 6

Cheers.

Simplify. Show your work 9x5+4=

Answers

Answer:

49 or 7^2

Step-by-step explanation:

9 x 5 + 4

=> 45 + 4

=> 49 or 7^2

Answer: 49

Step-by-step explanation: Multiply 9 and 5. Then add 4. Use PEMDAS.

9 × 5 = 45

45 + 4 = 49

Which of the following is equal to the opposite of −45? −(−45) −45 −|−45| −|45|

Answers

Answer:

−(−45)

I hope this helps.

Answer:

−(−45)

Step-by-step explanation:

Nadia determines that there are no fractions equivalent to 2/10 with a denominator greater than 10, but less than 20, that have a whole number numerator and denominator. Is she correct?

Answers

Answer:

No, Nadia is incorrect. She could multiply both the numerator and denominator of the unit fraction equivalent to 2/10 by 3 and arrive at the equivalent fraction 3/15.

*Credits to another Brainly question. The person who asked the question put this answer in the answer options.*

1. Rylan's basketball team has 11 players.How many ways can his coach choose five
starting players?

2. Sarah plays softball over the summer. If there are 10 players on the team, how
many ways can the coach make a batting order?

Answers

Answer:

Hey there!

For question 1:

C(11,5) = (11!)/(5!*(11-5)!)

C(11,5) = (11!)/(5!*6!)

C(11,5) = (11*10*9*8*7*6!)/(5!*6!)

C(11,5) = (55440)/(120)

C(11,5) = 462 ways

For question 2:

10!=10*9*8*7*...*2*1= 3628800 ways.

This can be a challenging and confusing topic, so let me know if you want a easier to understand explanation, I'm always here to give one :)

A number of ways to choose the players are 462 and The coach made a batting order is 3,268,800.

What is permutation?

A permutation is an act of arranging the objects or elements in order.

1.  Rylan's basketball team has 11 players.

His coach chooses five starting players.

The number of different ways to choose the players.

[tex]\rm ^{11}C_{5} = \dfrac{11!}{5! (11-5)!} = 462[/tex]

2.  Sarah plays softball over the summer. If there are 10 players on the team.

The coach made a batting order that will be

[tex]10! = 10*9*8*7*6*5*4*3*2*1 = 3268800[/tex]

Thus, A number of ways to choose the players are 462 and The coach made a batting order is 3,268,800.

More about the permutation link is given below.

https://brainly.com/question/1216161

Simplify,, Explantion if possible

Answers

Answer: 3

Explanation:

I added a picture please check it out

Answer:

work is shown and pictured

15. (01.01)
What is the value of the radius of the following circle with an area of 154 cm2? (1 point)
Area

154 cm^2

*4.9 cm
*7.0 cm
*25 cm
*68 cm​

Answers

Answer:

The answer is option B

Step-by-step explanation:

Area of a circle = πr²

where

r is the radius of the circle

From the question

Area = 154cm²

To find the radius substitute this value into the above formula and solve for the radius

That's

154 = πr²

Divide both sides by π

We have

[tex] {r}^{2} = \frac{154}{\pi} [/tex]

Find the square root of both sides

Thats

[tex]r = \sqrt{ \frac{154}{\pi} } [/tex]

r = 7.0014086

We have the final answer as

radius = 7.0 cm

Hope this helps you

NEED HELP ASAP!! I need to find out x!! Trigonometry!!

Answers

Answer:

Hey there!

Well first, don't feel bad, since trig is really hard, especially if you are just learning it.

If you've learned about SOH CAH TOA, you will see that TOA is the best identity to use here.

tangent 20=x/10

tangent 20 (10)=x

x=3.64

Let me know if you have any other trig questions, I'm always here to help :)

When two lines crosses, it is found that the angle opposite each other are thesame sizes. They are known as what

Answers

Answer:

vertical angles

Step-by-step explanation:

Opposite angles that are congruent are known as vertical angles.

If a = 5 b = 3 and c = 2
2ab =

Answers

Answer:

30

2ab=2*5*3

30

hope it helps

Answer:

30

The equation re-written would be

2 · 5 · 2 = 30

Glorias teacher asks her to draw a triangle with 90 degree angle and a 42 degree angle. How many unique triangles can Gloria draw that meet her teachers requirements

Answers

Answer:

Just two

Step-by-step explanation:

Glorias teacher asks her to draw a triangle with 90 degree angle and a 42 degree angle.

The presence of 90 degrees indicates that it's a right angle triangle.

The remaining angle= 180-90-42

The remaining angle= 48 degrees

Due to the presence of 90 degrees, the angle 42 and 48 degrees will interchange two times only to form only two unique triangles.

Which One Doesn't Belong?
3x - 5
12x
1 + x
x2 + 5x + 6

Answers

3x-5 does not belong

Reasoning :

Plug in “1” to each X unit

3(1) -5 = -2
12(1) = 12
1 + (1) = 2
(1)2 + 5(1) + 6 = 13

all are positive except 3x-5

so 3x-5
Other Questions
Wright Company's cash account shows a $28,900 debit balance and its bank statement shows $27,200 on deposit at the close of business on May 31. The May 31 bank statement lists $170 in bank service charges; the company has not yet recorded the cost of these services.Wright Company deposits all cash receipts on the day when they are received and it makes all cash payments by check. At the close of business on May 31, 2013, its Cash account shows a $28,900 debit balance. The companys May 31 bank statement shows $27,200 on deposit in the bank.a. The May 31 bank statement included a $170 debit memorandum for bank services; the company has not yet recorded the cost of these services.b. Outstanding checks as of May 31 total $6,300.c. May 31 cash receipts of $6,900 were placed in the banks night depository after banking hours and were not recorded on the May 31 bank statement.d. In reviewing the bank statement, a $470 check written by Smith Company was mistakenly drawn against Wrights account.e. A debit memorandum for $460 refers to a $460 NSF check from a customer; the company has not yet recorded this NSF check.Prepare a bank reconciliation for the company using the above information. which ides could the cherry blossoms symbolize in lovliest of trees the cherry now if ABCD is a parallelogram find the value of unknown size of angle Which two equations below are equivalent to 4x-4?Group of answer choices3x+x+12-166(x-2)-2x+84x+14-104x-3x+2-4 Which statement describes the congruent triangles?1. WXZ = YZX2. WXZ = YXZ3. WXZ = XYZ4. WXZ =ZYX Convert the distance in 1,200,000,000 kilometers from earth to meters in scientific notation What rights did the Civil Rights Act of 1866 grant all citizens? Check all of the boxes that apply. answer is the right to own property the right to present evidence in court the right to equal protection of the law You have a function that takes in an X value and produces a Y value. The y value equals 24 times the x value, plus 4 more. What's the y value when the x value equals 4? What is 3.5z - 2.7z = -6 What is Z. show all steps when completing the square to solve 2x^2 - 4x - 5 = 25 Simplify by dividing negative three over eight divided by five over nine.. The difference of twice a number and 3 is -21 translated Using the map above, what number is on the state with the capital city of Phoenix?Please help ASAP!!!!! Round the whole number 4,205 to the tens place A brittle material typically exhibits substantial plastic deformation with high energy absorption before fracture.a) trueb) false 10. Read the following hypothesis: Plants that receive too much water will not grow well because their rootsbegin to rot. Suppose an investigation is planned to explore the hypothesis. What is the independentvariable of the investigation?the amount of water given to the plantsthe type of plant that is used in the experimentthe height of the plants at the end of the experimentthe mass of the plants at the end of the experiment The mass of a body on the surface of the earth is 12kg. If acceleration due to gravity onmoon is 1/6 of acceleration due to gravity on earth, then its mass on moon will be:a)2kgb)12kgc)72kgd)zero what is digestive system Each side of a sandbox is 7 feet long. It will cost $1.00 per square foot to replace the sand in the sandbox. What would be the total cost to replace the sand? is x^2+y^2=5 a function? why or why not?