PLEASE HELP FAILING ...A random variable x has a mean of 22 and a standard deviation of 3.1. Random samples of size 40 are drawn, and the sample mean calculated each time. What is the probability that, for a given sample, is 21?

Answers

Answer 1

The sample sizes are quite large, so the central limit theorem applies. (It typically does as soon as the sample size exceeds 30 or so.) This means that the sample mean will be approximately normally distributed with the same mean 22 but standard deviation 3.1/√40 ≈ 0.4902.

Now, if the question is asking about the probability of the sample mean being an exact number, that probability would be zero.

But if you meant to ask something else, like "what is the probability that the sample mean is less than 21?" then we would have a non-zero probability. In this particular case, if Y is a random variable for the sample mean, then

Pr[Y < 21] = Pr[(Y - 22)/(3.1/√40) < (21 - 22)/(3.1/√40)]

… ≈ Pr[Z < -2.0402]

… ≈ 0.0207


Related Questions

The dimensions of a trapezoid are halved.
a) How will the area be affected?
b) If the area of the original trapezoid is 28 cm?, then what will the area of the smaller
trapezoid be?
Draw or add images here

Answers

Answer:

  a) area will be 1/4 of the original

  b) 7 cm²

Step-by-step explanation:

a)

Consider the equation for the area of a trapezoid:

  A = 1/2(b1 +b2)h

Now, halve each of the dimensions:

  A' = 1/2((1/2)b1 +(1/2)b2)((1/2)h)

  A' = (1/4)(1/2(b1 +b2)h) = 1/4A

The area is multiplied by the square of the scale factor: (1/2)² = 1/4.

__

b)

The area of the smaller trapezoid will be ...

  A' = 1/4A = (1/4)(28 cm²) = 7 cm²

Divide 63.5 ÷ 0.25 round the quotient to the nearest ten-thousandth

Answers

Answer:

254

Step-by-step explanation:

63.5 ÷ 0.25 =

= 63.5 ÷ 1/4

= 63.5 × 4

= 254

Answer: 254.

How do you make a mixed fraction and write it out as a improper fraction?

Answers

Answer:

1) Multiply the whole number part by the fraction's denominator.

2) Add that to the numerator.

3) Then write the result on top of the denominator.

Step-by-step explanation:

Hope this helps!

Answer:

Explanation

|

Step-by-step explanation:

you you multiply the whole number by the denominator and then add the numerator to that number.

Diets For You announced today that it will begin paying annual dividends next year. The first dividend will be $0.12 a share. The following dividends will be $0.15, $0.20, $0.50, and $0.60 a share annually for the following 4 years, respectively. After that, dividends are projected to increase by 4 percent per year. How much are you willing to pay to buy one share of this stock today if your desired rate of return is 8.5 percent?

Answers

You will be willing to pay $ 1.41 to buy one share of this stock today if your desired rate of return is 8.5 percent.

Since Diets For You announced today that it will begin paying annual dividends next year, and the first dividend will be $ 0.12 a share, and the following dividends will be $ 0.15, $ 0.20, $ 0.50, and $ 0.60 a share annually for the following 4 years, After that, dividends are projected to increase by 4 percent per year, to determine how much are you willing to pay to buy one share of this stock today if your desired rate of return is 8.5 percent, the following calculation must be performed:

8.5 = 0.12 100 = X 100 x 0.12 / 8.5 = X 1.41 = X

Therefore, you will be willing to pay $ 1.41 to buy one share of this stock today if your desired rate of return is 8.5 percent.

Learn more about maths in https://brainly.com/question/25989093


(3x - 4x - 2 + 3x - 6 = 180
7x – 8 =

Answers

If we collect like terms of the first equation, we can simplify to

2x - 8 = 180

If we add 8 to both sides, we get

2x = 188

And that means x = 94

If we substitute this into the second equation, we get

7(94) - 8 = ?

7 x 94 is equal to 658

658 - 8 = 650

Bidmass working out questions

Answers

Answer:

The answer will be 0

Step-by-step explanation:

Let me know Hope it helps

help me out guys !!!!!!​

Answers

Answer:

[tex]2\sqrt[3]{5}[/tex]

Step-by-step explanation:

40 = 8 x 5 and 8 is the cube of 2, so 2 goes on the outside but 5 can't be simplified

The backyard of a new home is shaped like a trapezoid with a height of 44 nt and bases of 86ft and 106ft What is the cost of putting sod on the yard, if the
landscaper charges $0.25 por square foot for sod?

Answers

Answer:

Step-by-step explanation:

Area of a trapezoid is the average length of the bases times the height

C = A(0.25)

A = ½(86 + 106)(44) = 4224 ft²

C = 4224(0.25) = $1056.00

find the rate of change
input 1 2 3 4 5
output 11 13 15 17 19

Answers

Answer:

  2

Step-by-step explanation:

x-values in the table increase by 1, while y-values increase by 2. The rate of change is ...

  m = slope = rate of change = (change in y)/(change in x) = 2/1 = 2

The rate of change is 2.

Answer:2

Step-by-step explanation:

Your family has a total of 60 t-shirts and you decide to give some away. If 4 of the t-shirts are being worn right now, and there are 25 t-shirts left in the family's closets, how many t-shirts did your family give away?

Answers

You gave away 35 shirts. 60-25=35.

31

If you had 60 t-shirts and wore 4 and had 25 you do 25+4=29 then you do 60-29 that =31 so you will have sold 31 t-shirts

Someone please help me!

Answers

y is 15 and x is 34, i hope that helped

2. Find the equation of the perpendicular bisector of line PQ where the co-ordinates of P and Q are P (-2, 8) and Q (4,7)

Answers

Answer:

2y - 12x = 3

Step-by-step explanation:

gradient of line PQ= (7-8)/ 4+2

-1/6

gradient of perpendicular bisector of line PQ=

-1 ÷ -1/6

-1× -6

6

coordinates of the midpoint of line PQ

(-2+4)/2, (8+7)/2

(1, 15/2)

the perpendicular bisector passes through the midpoint of line PQ

Equation of the perpendicular bisector

y - 15/2 = 6(x - 1)

multiply through by 2

2y - 15 = 12(x - 1)

2y - 15 = 12x - 12

2y - 12x = 3

After Arianna completed some work, she figured she still had 78.09 pictures to paint. If she completed another 34.23 pictures, how many pictures does Arianna still have to paint? Convert the mixed numbers into decimals before calculating the sum or difference.

Answers

Answer:

43.86

Step-by-step explanation:

that's da awnserrr

Hi guys can u guys help me add 322 + 12

Answers

Answer:

334 is the answer

Step-by-step explanation:

you add them together

Answer:

334 is the right answer

Step-by-step explanation:

please mark me brainliest

Please help solve this

Answers

Answer:

LCD= x²- 81

Step-by-step explanation:

x²-81 is difference of two squares

a²-b²= (a+b)(a-b)

x²- 81= (x+9)(x-9)

denominators, (x-9) and (x+9)(x-9)

x-9 is common in both denominators

x-9|(x-9)|(x+9)(x-9)

x+9| 1 | x+9

| 1 | 1

therefore the LCD= (x-9)(x+9)

simplifying= x²- 81

I’m pretty sure the answer would be81

6 divided by x squared​

Answers

Answer:

I think x should be equal to 0.

Elements that do not belong to a set belong to its

Answers

Answer:

What do you mean for this question?

Step-by-step explanation:

Give specific details

Genes are sections of DNA that code for a particular trait. Genes are?

Answers

Answer:

Genes are DNA transferred to off spring by parents

Answer:

Genes are sections of DNA that code for a particular trait. Genes are nucleic acids.

Step-by-step explanation:

Pls help me its a little confusing

Answers

Answer:

the measure of x is 38

Step-by-step explanation:

180-134=46 the value of one side of a line is 180 degrees so to find the vaule                of the inside angle we have to subtract 180 by the outside angle's

180-84=96

46+96=142 we then add the value's of both inside angles

180-142= 38

then we subtract that number by 180 because the total of all three angles of any triangle is always 180

Answer:

x = 38°

Step-by-step explanation:

Maths problem always go back to a number of foundational rules;

Once you recognise the ones that are relevant, you can then apply them to find the value or solution you want to find;

First thing is to look at the question and information provided in order to identify the relevant rules;

This question is asking for an angle and we can see a triangle (not a right-angle triangle) and line beneath it;

What rules should we think of with this in mind?

The following;

Angles in any triangle always add to 180°Angles on a straight line add to 180°

Using these rules, we can find x;

Firstly, according to rule 2, we can find angle OLM:

134 + OLM = 180

OLM = 180 - 134

OLM = 46

Secondly, also according to rule 2, we can find angle OML:

84 + OML = 180

OML = 180 - 84

OML = 96

Lastly, according to rule 1, we can find angle x:

OLM + OML + x = 180

46 + 96 + x = 180

x = 180 - 96 - 46

x = 38

I NEED HELP!!

If f(x) = x 3/2 , then f ' (4) =

A. -6
b. -3
c. 3
d. 6
e. 8

Answers

Answer:

f(x)=x(3/2)

f(4)=4*3/2

6

ricky is a hardworking man who owns 6 hectares of land. in his will,he divided his lot equally among 7 sons. how much land will each of his son receive?
a. 0.68
b. 0.86
c. 68
d. 86 ​

Answers

Question:-

ricky is a hardworking man who owns 6 hectares of land. in his will,he divided his lot equally among 7 sons. how much land will each of his son receive?

a. 0.68

b. 0.86

c. 68

d. 86

Answer:-

Given,

Land owned by Ricky = 6 hectares

No. of sons = 7

Now,

6 ÷ 7 = 0.8571429 or 0.86

Each son will own 0.86 hectares of land. Option b. 0.86 is the answer.

Order the numbers from least to greatest

Answers

Step-by-step explanation:

(|  |) makes the number opposite

|10|=-10

|-3|=3

|0|=0

|-5.25|=5.25

Least to greatest

|10|, |0|, |3|, |5.25|

Let me know if there's any mistakes

The body mass index, I, can be used to determine an individual's risk for heart disease. An index less than 25 indicates a low risk. The body mass index is given by
700W
the formula, or model, I=
where W= weight, in pounds, and H = height, in inches. Jerome is 70 inches tall. What weights will keep his body mass index
H2
between 20 and 28?

Answers

Using the BMI equation, it is found that weights between 139.4 and 195.2 pounds will keep his BMI between 20 and 28.

The BMI B, for a person of weight w(in pounds) and height h(in inches) is given by:

[tex]BMI = \frac{703w}{h^2}[/tex]

In this problem:

Height of 70 inches, hence [tex]h = 70[/tex].

For a BMI of 20 inches, the weight is:

[tex]BMI = \frac{703w}{h^2}[/tex]

[tex]20 = \frac{703w}{70^2}[/tex]

[tex]w = \frac{20 \times 70^2}{703}[/tex]

[tex]w = 139.4[/tex]

For a BMI of 28 inches, the weight is:

[tex]BMI = \frac{703w}{h^2}[/tex]

[tex]28 = \frac{703w}{70^2}[/tex]

[tex]w = \frac{28 \times 70^2}{703}[/tex]

[tex]w = 195.2[/tex]

Weights between 139.4 and 195.2 pounds will keep his BMI between 20 and 28.

To learn more about the BMI, you can take a look at https://brainly.com/question/24457127

Use the distributive property to write an experssion that is equalent to 10+15x

Answers

Answer:

5(2+3x)

Step-by-step explanation:

5 x 2 = 10

5 x 3x = 15x

10+15x

(PEMDAS)

Answer:

Step-by-step explanation:

im a boy

Today, both the soccer team and the basketball tear
had games. The soccer team plays every 3 days and the
basketball team plays every 5 days. When will both
teams have games on the same day again?


SHOW YOUR WORK PLEASE

Answers

On the 15th day

Explanation

You have to find which multiple they have the same and that would be 15

3: 3, 6, 9, 12, 15, 18, 21 and so on
5: 5, 10, 15, 20, 25 and so on

Answer:3 to 5

Step-by-step explanation:i took the quiz

40% of the plants in Marcy's garden are root vegetables. If 20 plants are root vegetables, how many plants are in Marcy's garden in all?

Answers

Answer:

dont do anything if im wrong but i thinks its 50 plants

Step-by-step explanation:

E


(g, 6) and (-5, -9)

Slope = 3/2

Answers

Answer:

g=5

Step-by-step explanation:

(-9)-(6) / (-5)-(g) = 3/2

3 x -(g+5) = 2 x -15

g+5=10

g=5

Answer:

g=15

Step-by-step explanation:

we first can substitute in (-5,-9) into the x and y variables in y=mx+b as well as the slope:

so we get:

-9=3/2(-5)+b

now lets solve for b:

3/2 x -5 = -15/2

-9=-15/2+b

now add the -15/2 on both sides of the eqaution:

b=-33/2

now lets substitute it back in:

y=3/2x-33/2

NOW lol substitute the 6 in to find g:

6=3/2g-33/2

solve from here to get

45/2=3/2g

multiply by 2 on each side

45=3g

divide both sides by 3:

g=15!!!!!!!!!!!!!!

I hope this helped sry it took long lol

HELP! ( MATH )
WILL GIVE BRAINILEST!

Question:
Graph the solution of the equation.
b – 5 = –8

Answers

Answer:

b = -3 so A is answer

good luck

Answer:

option C is the correct answer

Which list of angle measures could be the angle measures of a triangle?

Answers

Answer:

D. 35, 60, 85

Step-by-step explanation:

All angles of a triangle have to add up to 180 degrees.

35+60+85 = 180

plss help me....... ​

Answers

Answer:

The slope

Step-by-step explanation:

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