A population is estimated to have a standard deviation of 9. We want to estimate the population mean within 2, with a 99% level of confidence. How large a sample is required? (Round up your answer to the next whole number.)

Answers

Answer 1

Answer:

The sample required is  [tex]n = 135[/tex]

Step-by-step explanation:

From the question we are told that

     The  standard deviation is  [tex]\sigma = 9[/tex]

      The margin of error is [tex]E = 2[/tex]

     

Given that the confidence level is  99%  then the level of  significance is mathematically evaluated as

         [tex]\alpha = 100-99[/tex]

        [tex]\alpha = 1 \%[/tex]

        [tex]\alpha = 0.01[/tex]

Next we will obtain the critical value  [tex]\frac{\alpha }{2}[/tex] from the normal distribution table(reference  math dot armstrong dot edu) , the value is  

             [tex]Z_{\frac{\alpha }{2} } = Z_{\frac{0.05 }{2} } = 2.58[/tex]

The  sample size is mathematically represented as

          [tex]n = [ \frac{Z_{\frac{\alpha }{2} } * \sigma }{E} ]^2[/tex]

substituting values

           [tex]n = [ \frac{ 2.58 * 9 }{2} ]^2[/tex]

            [tex]n = 135[/tex]


Related Questions

What would be the mass of a cube of tungsten (density of 19.3 g/cm), with sides of
3cm?

Answers

Answer:

M= 521.1 g

Step-by-step explanation:

1st.  Find the volume of the cube:   V=3³=27 cm³

As the weight of V= 1 cm³ cube  is 19.3 g the weight of the cube=27 cm³ is

M=27*19.3= 521.1 g

The value of 3 in 783.97

Answers

Answer:

place value of 3 in 783.97 is 3

Step-by-step explanation:

Answer:

Units

Step-by-step explanation:

The units start counting from 3 because after the point that is the 9 start counting tenth

Marking as brainyest PLEASE HELP

How does f(x) = 9x change over the interval from x = 3 to x = 4? A) f(x) increases by 100% B) f(x) increases by 800% C) f(x) increases by 900% D) f(x) increases by 1000%

Answers

Answer:

C) f(x) increases by 900%

Step-by-step explanation:

The rate of change is

f(4) - f(3)

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

4-3

f(4) = 9*4 = 36

f(3) = 9*3 = 27

36 -27

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

4-3

9

-----

1

The rate of change is 9

To change to a percent, multiply by 100%

9*100% = 900%

Answer:

Increases by 900%

Step-by-step explanation:

● f(x) = 9x

The rate of change is:

● r = (36-27)/(4-3) = 9

So the function increses nine times wich is equivalent to 900%

Solve for W.
W/9 = g​

Answers

Answer:

W = 9 * g

Step-by-step explanation:

W/9 = g

W = 9 * g

The expression W/9 = g can be written as W = 9g after cross multiplication.

What is an expression?

It is defined as the combination of constants and variables with mathematical operators.

We have an expression:

W/9 = g

To solve for W

Make subject as W:

W = 9g

By cross multiplication.

Thus, the expression W/9 = g can be written as W = 9g after cross multiplication.

Learn more about the expression here:

brainly.com/question/14083225

#SPJ2

pls helpppp find the total area of the prism

Answers

Answer:

Total area = [tex](54+\frac{9\sqrt{3} }{2})[/tex] square inch

Step-by-step explanation:

Total area of the prism = Area of the rectangular sides (lateral sides) + area of the triangular bases

Area of the rectangular sides = 3 × (length × width)

                                                 = 3 × (3 × 6)

                                                 = 54 square inch

Area of the triangular bases = 2 × (Area of an equilateral triangle)

                                               = 2 × [tex]\frac{\sqrt{3}}{4}(\text{Side})^2[/tex]

                                               = [tex]\frac{\sqrt{3}}{2}(\text{Side})^2[/tex]

                                               = [tex]\frac{\sqrt{3}}{2}(3)^2[/tex]

                                               = [tex]9(\frac{\sqrt{3} }{2})[/tex]

                                               = [tex]\frac{9\sqrt{3}}{2}[/tex] square inch

Total surface area = (54 + [tex]\frac{9\sqrt{3}}{2}[/tex]) square inch

Answer two questions about Equations A and B:
A. 2x-1=5x
B. -1=3x

1) How can we get Equation B from Equation A?

Choose 1 answer:

Add/subtract the same quantity to/from both sides

Add/subtract a quantity to/from only one side

Rewrite one side (or both) by
combining like terms

Rewrite one side (or both) using the distributive property

NEXT QUESTION
based on the previous answer, are the equations equivalent? In other words, do they have the same solution?

A. Yes
B. No

Answers

Answer:

B: Add/subtract the same quantity to/from both sides

Next Question: Yes

Step-by-step explanation:

thats what the answer is dunno what else to tell you lol

Algebraic equations are mathematical equations that contain unknown variables.

To get Equation B from Equation A, we add/subtract the same quantity to/from both sides. Option A is the correct option. Equation A is equivalent to Equation B

Question 1: We are given equation A as:

2x - 1 = 5x .............Equation A

To get Equation B from A, we would subtract 2x from both sides of the equation.

2x - 2x - 1 = 5x - 2x

- 1 = 3x This is Equation B

Question 2: Based on the previous answer,

2x - 1 = 5x  is equal to  -1 = 3x.

Hence, both Equation A and Equation B are equivalent expressions.

Therefore,

To get Equation B from Equation A, we add/subtract the same quantity to/from both sides. Option A is the correct option.Equation A is equivalent to Equation B

To learn more, visit the link below:

https://brainly.com/question/22299566

What is the radius of the circle whose center is the
origin and that passes through the point (5,12)?

Answers

Answer:

13 units

Step-by-step explanation:

Use the equation of a circle, (x - h)² + ( y - k )² = r², where (h, k) is the center and r is the radius.

Plug in the values and solve for r:

(5 - 0)² + (12 - 0)² = r²

25 + 144 = r²

169 = r²

13 = r

what should be added to 66.778 get 78.2​

Answers

Answer:

11.422

Step-by-step explanation:

[tex]78.2 - 66.778 \\ = 11.422[/tex]

Solve the equation for the given variable x/4=6/8

Answers

Answer:

x = 3

Step-by-step explanation:

This process is called cross multiplication.

Multiply 6 · 4 = 24

Divide 24 ÷ 8 = 3

x = 3

Answer:

x = 3

Step-by-step explanation:

x/4 = 6/8

Using cross products

x*8 = 4*6

8x = 24

Divide by 8

8x/8 = 24/8

x = 3

what is sum of all palindromic numbers from 1 to 100 ​

Answers

Answer:

540

Step-by-step explanation:

0 + 1 + 2 + 3 + 4 + 5 + 6 + 7 + 8 + 9 + 11 + 22 + 33 + 44 + 55 + 66 + 77 + 88 + 99

Answer:

540

Step-by-step explanation:

Hey there!

Well we need to first find all the palindromic numbers,

0, 1, 2, 3, 4, 5, 6, 7, 8, 9, 11, 22, 33, 44, 55, 66, 77, 88, 99

Add

= 540

Hope this helps :)

A slot machine has 3 dials. Each dial has 30 positions, one of which is "Jackpot". To win the jackpot, all three dials must be in the "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

since there are 3 slots and each slot has 30 positions:

dial 1 can have a max of 30 possible outcomes, and so can dial 2 and 3

hence all the dial have 30 possible outcomes

total combinations = total outcomes of slot 1 X total outcomes of slot 2 X total outcomes of slot 3/ 3!

total combinations = 30 * 30 * 30 / 3 X 2 X 1

total combinations = 9000/3 X 2

total combinations  = 1500

hence, there is a total of 1500 different combinations of the 3 slots

the combination required is 1 from the 1500

hence the odds are  1/1500

Answer:

1/27000

Step-by-step explanation:

30*30*30 =27000

each dial has to be in correct position so 1/27000 is correct

Please help with this

Answers

Answer:

A

Step-by-step explanation:

● first one:

The diagonals of a rhombus are perpendicular to each others wich means that they form four right angles.

STP is one of them so this statement is true.

● second one:

If ST and PT were equal this would be a square not a rhombus.

● third one:

If SPQ was a right angle, this woukd be a square.

● fourth one:

Again if the diagonals SQ and PR were equal, this would be a square.

What is the rectangular form of the polar equation?
0=-
57
y=x
V3
Oy= 32
y=-3x

Answers

Answer:

Option (1)

Step-by-step explanation:

From the picture attached,

tanθ = [tex]\frac{y}{x}[/tex]

Given : Polar equation as 'θ' = [tex]-\frac{5\pi }{6}[/tex]

Therefore, [tex]\text{tan}(-\frac{5\pi }{6} )[/tex] = [tex]\frac{y}{x}[/tex]

[tex]-\text{tan}(\frac{5\pi }{6} )[/tex] = [tex]\frac{y}{x}[/tex]   [Since tan(-θ) = -tanθ]

[tex]\text{tan}(\pi -\frac{5\pi }{6} )[/tex] = [tex]\frac{y}{x}[/tex] [Since -tanθ = tan(π - θ)]

[tex]\text{tan}\frac{\pi }{6}[/tex] = [tex]\frac{y}{x}[/tex]

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

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

Therefore, y = [tex]\frac{\sqrt{3} }{3}x[/tex] will be the rectangular form of the polar equation.

Option (1) will be the correct option.

please help me answer these questions :(

Answers

Answer:

a) ∠X = 67.4°

ii) ∠Y = 22.6°

b) Hypotenuse = 13 miles

ii) Length of each congruent = 4.33 miles

c) Distance of mall from point A = 5.21 miles

d) Distance os mall from point B = 8.17 miles

e) Difference = 2.96 miles

ii) Amount it will cost = $1,628,000

Step-by-step explanation:

Because of the length of the solution, I sent it as an attachment to this answer.

An empty swimming pool is to be filled to the top. The pool is shaped like a rectangular prism with length 10m, width 8m , and depth 4m. Suppose water is pumped into the pool at a rate of 16m cubed per hour. How many hours does it take to fill the empty pool?

Answers

Answer:

20 hours

Step-by-step explanation:

10*8*4=320 (volume of the pool)

320/16=20 hours

Answer:

20 hours

Step-by-step explanation:

10x8x4 = 320

320 / 16 = 20

it takes 20 hours to fill the empty pool

Find the slope of the line whose x-intercept is 4 and the y- intercept is -9

Answers

Answer:

y = (9/4)x - 9

Step-by-step explanation:

The x-intercept is (4, 0) and the y-intercept is (0, -9).

As we move from (0, -9) to (4, 0), x (the 'run' increases by 4 and y (the 'rise' increases by 9.  Thus, the slope of the line connecting these two points is m = rise/run = 9/4, from which we can write the desired equation in the form y = mx + b:

y = (9/4)x - 9

What is the percentage of 204 over 1015, 1 over 8120, 1 over 5832, and 1 over 6?

Answers

Answer:

204/1015 (irreducible) = 20.1%

1/8120 (irreducible) = 0.01232%

1/5832 (irreducible) = 0.01715%

1/6 (irreducible) = 16.67%

Step-by-step explanation:

I suck at math, online school is really hard I need to find a tutor, can this be explained?

Answers

Answer:

its [c] if Bradley serves 4 tables he will earn an average of $25

Step-by-step explanation:

1) Given P(A) = 0.3 and P(B) = 0.5, do the following.
(a) If A and B are mutually exclusive events, compute P(A or B).
(b) If P(A and B) = 0.2, compute P(A or B).
2) Given P(A) = 0.4 and P(B) = 0.2, do the following.
(a) If A and B are independent events, compute P(A and B).
(b) If P(A | B) = 0.7, compute P(A and B).

Answers

Answer:

1) a) 0.8

b) 0.6

2) a) 0.08

b) 0.14

Step-by-step explanation:

1) Given

[tex]P(A) = 0.3[/tex] and [tex]P(B) = 0.5[/tex]

Let us learn about a formula:

[tex]P(A\ or\ B) = P(A) +P(B) -P(A\ and\ B)\\OR\\P(A\cup B) = P(A) +P(B) -P(A\cap B)[/tex]

(a) If A and B are mutually exclusive i.e. no common thing in the two events.

In other words:

[tex]P(A\ and\ B)[/tex] = [tex]P(A \cap B)[/tex] = 0

Using above formula:

[tex]P(A\ or\ B) = P(A) +P(B) -P(A\ and\ B)\\\Rightarrow P(A\ or\ B) = 0.3 + 0.5 -0 = \bold{0.8}[/tex]

(b)  P(A and B) = 0.2

Using above formula:

[tex]P(A\ or\ B) = P(A) +P(B) -P(A\ and\ B)\\\Rightarrow P(A\ or\ B) = 0.3 + 0.5 -0.2 = \bold{0.6}[/tex]

*************************************

1) Given

[tex]P(A) = 0.4[/tex] and [tex]P(B) = 0.2[/tex]

Let us learn about a formula:

[tex]P(A\ and\ B) = P(B) \times P(A/B)[/tex]  for dependent events

[tex]P(A\ and\ B) = P(A) \times P(B)[/tex] for independent events.

(a) If A and B are independent events :

Using the above formula for independent events:

[tex]P(A\ and\ B) = 0.4 \times 0.2 = \bold{0.08}[/tex]

(b)  [tex]P(A / B) = 0.7[/tex]

Using above formula:

[tex]P(A\ and\ B) = P(B) \times P(A/B) = 0.2 \times 0.7 = \bold{0.14}[/tex]

-50 POINTS- please help

Answers

Answer:

-13

-10

Step-by-step explanation:

A x = B

To find X

A ^ -1 A  x = A ^ -1 B

x = A^ -1 B

x = -3/2  -5/2      2

     -1       -2         4

Across times down

-3/2 * 2 + -5/2 *4 = -13

-1 *2 -2 * 4 = -10

The matrix is

-13

-10

Answer:

[tex]\Large \boxed{\bold{D.} \ \left[\begin{array}{ccc}-13\\ -10\end{array}\right]}[/tex]

Step-by-step explanation:

[tex]AX=B[/tex]

To find [tex]X[/tex]

[tex]X=A^{-1} \cdot B[/tex]

[tex]\displaystyle \left[\begin{array}{ccc}-\frac{3}{2} \cdot 2 + - \frac{5}{2} \cdot 4\\ -1 \cdot 2 + -2 \cdot 4\end{array}\right][/tex]

[tex]\displaystyle \left[\begin{array}{ccc}-3 + - 10\\ -2 + -8\end{array}\right][/tex]

[tex]\displaystyle \left[\begin{array}{ccc}-13\\ -10\end{array}\right][/tex]

The quotient of 8 and the difference of three and a number​.
Answer: 8÷(3-x)

Answers

Answer:

Below

Step-by-step explanation:

● 8 ÷ (3-x)

Dividing by 3-x is like multiplying by 1/(3-x)

● 8 × (1/3-x)

● 8 /(3-x)

if f(x)=3-2x and g(x)= 1/x+5 what is the value of (f/g) (8)​

Answers

Answer:

Step-by-step explanation:

(f/g) = (3 - 2x ) / (1/x + 5) You could go to the trouble to simplify all of this, but the easiest way is to just put in the 8 where you see an x

(f/g)8 = (3 - 2*8) / (1/8 + 5)

(f/g)/8 = (3 - 16 / (5 1/8)          1/8 = 0.125

(f/g) 8 = - 13 / ( 5.125)

(f/g)8 = - 2.54

Find the area of the irregularly-shaped hexagon below

Answers

let each box length be 1

for white triangle

area = ½bh

=½(4)(2)

=4

for orange triangle

area=½(2)(3)

=3

for blue marked boxes

each of the box

area=l²

=(1)²

=1

there are 16 boxes

so the total area will be 16

total area of the hexagon = 4+3+16

=23 square units

[tex]A_1=\dfrac{1}{2}(3+5)\cdot 3=12\\A_2=1\cdot5=5\\A_3=\dfrac{1}{2}(5+1)\cdot 2=6[/tex]

So the area of the whole shape is [tex]12+5+6=23[/tex]

find the value of X from the given picture ​

Answers

Answer:

x = 108

Step-by-step explanation:

The sum of a circle is 360

90 + x/2 + x+x = 360

Combine like terms

90 + 2x+x/2 = 360

90 + 5/2 x = 360

Subtract 90 from each side

5/2x = 270

Multiply each side by 2/5

5/2x * 2/5 = 270*2/5

x =108

If the legs of an isosceles right triangle have a length of 15 StartRoot 2 EndRoot ft, what is the length of the hypotenuse?

Answers

Answer:

30 ft

Step-by-step explanation:

a² + b² = c²

(15sqrt(2))² + (15sqrt(2))² = c²

225 * 2 + 225 * 2 = c²

c² = 900

c = sqrt(900)

c = 30

Answer: 30 ft

Answer:

30 ft

Step-by-step explanation:

a² + b² = c²

(15sqrt(2))² + (15sqrt(2))² = c²

225 * 2 + 225 * 2 = c²

c² = 900

c = sqrt(900)

c = 30

Answer: 30 ft

For each ordered pair, determine whether it is a solution to y=-9.
Is it a solution?
Yes or No
(1, -9)
(7,3)
(-9,4)
(0, -9)

Answers

Answer:

(1, -9)  yes

(7,3)  no

(-9,4)  no

(0, -9) yes

Step-by-step explanation:

The y value must be -9

The x value can be any value to satisfy   the equation y = -9

In a lottery game, a player picks 6 numbers from 1 to 50. If 5 of the 6 numbers match those drawn, the player wins second prize. What is the probability of winning this prize

Answers

Answer:

1/254,251,200 Or 0.000000003933118

Step-by-step explanation:

1/50x1/49x1/48x1/47x1/46=1/254,251,200

A new fast-food firm predicts that the number of franchises for its products will grow at the rate dn dt = 6 t + 1 where t is the number of years, 0 ≤ t ≤ 15.

Answers

Answer:

The answer is "253"

Step-by-step explanation:

In the given- equation there is mistype error so, the correct equation and its solution can be defined as follows:

Given:

[tex]\bold{\frac{dn}{dt} = 6\sqrt{t+1}}\\[/tex]

[tex]\to dn= 6\sqrt{t+1} \ \ dt.....(a)\\\\[/tex]

integrate the above value:

[tex]\to \int dn= \int 6\sqrt{t+1} \ \ dt \\\\\to n= \frac{(6\sqrt{t+1} )^{\frac{3}{2}}}{\frac{3}{2}}+c\\\\\to n= \frac{(12\sqrt{t+1} )^{\frac{3}{2}}}{3}+c\\\\[/tex]

When the value of n=1 then t=0

[tex]\to 1= \frac{12(0+1)^{\frac{3}{2}}}{3}+c\\\\ \to 1= \frac{12(1)^{\frac{3}{2}}}{3}+c\\\\\to 1-\frac{12}{3}=c\\\\\to \frac{3-12}{3}=c\\\\\to \frac{-9}{3}=c\\\\\to c=-3\\[/tex]

so the value of  n is:

[tex]\to n= \frac{(12\sqrt{t+1} )^{\frac{3}{2}}}{3}-3\\\\[/tex]

when we put the value t= 15 then,

[tex]\to n= \frac{(12\sqrt{15+1} )^{\frac{3}{2}}}{3}-3\\\\\to n= \frac{(12\sqrt{16} )^{\frac{3}{2}}}{3}-3\\\\\to n= \frac{(12\times 64)}{3}-3\\\\\to n= (4\times 64)-3\\\\\to n= 256-3\\\\\to n= 253[/tex]

Solve for x: −3x + 3 −1 b. x −3

Answers

Answer:

2/3

Step-by-step explanation:

Your −3x + 3 −1 is not an equation and thus has no solution.

If, on the other hand, you meant

−3x + 3 = 1

then -3x = -2, and  x = 2/3

What is the simplified form of x minus 5 over x squared minus 3x minus 10⋅ x plus 2 over x squared plus x minus 12 ? (6 points) Select one: a. 1 over the quantity x minus 3 times the quantity x plus 4 b. 1 over the quantity x minus 3 times the quantity x plus 2 c. 1 over the quantity x plus 4 times the quantity x minus 5 d. 1 over the quantity x plus 2 times the quantity x minus 5

Answers

Answer:

  [tex]\ \text{a. }\quad\dfrac{1}{(x-3)(x+4)}[/tex]

Step-by-step explanation:

Maybe you want the product ...

  [tex]\dfrac{x-5}{x^2-3x-10}\cdot\dfrac{x+2}{x^2+x-12}=\dfrac{x-5}{(x-5)(x+2)}\cdot\dfrac{x+2}{(x-3)(x+4)}\\\\=\boxed{\dfrac{1}{(x-3)(x+4)}}[/tex]

__

Numerator factors of (x-5) and (x+2) cancel those in the denominator.

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