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

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

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

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

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]

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 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.

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

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

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.

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.

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

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.

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]

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 :)

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)

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:

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

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]

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

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]

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

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

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%

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

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

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:

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

Other Questions
Jack oversees two very different workers. Kenny wants to be told exactly what to do because he is hesitant to make decisions, and Laila wants to be told exactly what to do because she wants to get on with it. So, even though they are very different people, they both respect decisiveness. According to the path-goal theory of leadership, Jack should use the _____________ leadership style with Kenny and Laila. A butterfly is flying around and its velocity(v) as a function of time(t) is given in the graph below where rightwards is the positive velocity direction. What is the butterfly's displacement x from t=2 to 4s? Answer with two significant digits. Prescription eye protection suitable for an electrician should always include a. a safety strap b. soft nose guards c. side shields d. tinted lenses E-tailers, such as Amazon and Expedia, that sell products and services directly to final buyers exclusively over the Internet are known as ________. 60feet to meters plaese with work You are asked to write an app to keep track of a relatively small music library. The app should load song information from a data file once the app is started. It should allow user to view, add, remove, and search for songs. The app should save the data back to the same data file when the program exits. "How many wavelengths wide must a single slit be if, at a point 8o from the central maximum, there is a 72 rad phase difference between the top and bottom rays?" Please answer this question now 13. If atoms from two different elements react to form a compound, the element with a highernumberwill have a negative oxidationA. atomic radiusB. energyC. electronegativityD. atomic number Apoptosis differs from necrosis in that necrosis:_______ a. requires the reception of an extracellular signal. b. causes DNA to fragment. c. causes cells to swell and burst, whereas apoptotic cells shrink and condense.d. involves a caspase cascade Read the excerpt from The Code Book. A theoretical breakthrough would be a fundamentally new way of finding Alice's private key. Alice's private key consists of p and q, and these are found by factoring the public key, N. The standard approach is to check each prime number one at a time to see if it divides into N, but we know that this takes an unreasonable amount of time. Which statement is best supported by this excerpt Given that H2(g)+F2(g)2HF(g)Hrxn=546.6 kJ 2H2(g)+O2(g)2H2O(l)Hrxn=571.6 kJ calculate the value of Hrxn for If m(x) =x+5/x-1 and n(x) = x - 3, which function has the same domain as (mn)(x)? Joe must pay liabilities of 1,000 due 6 months from now and another 1,000 due one year from now. There are two available investments: \,1. Bond I: a 6-month bond with face amount of 1,000, a 8% nominal annual coupon rate convertible semiannually, and a 6% nominal annual yield rate convertible semiannually; and \,2. Bond II: a one year bond with face amount of 1,000, a 5% nominal annual coupon rate convertible semiannually, and a 7% nominal annual yield rate convertible semiannually Calculate the amount of each bond Joe should purchase in order to exactly match the liabilities. Which is an example of a time-bound goal?Complete something in 90 days.Do something at noon every day.Take only five minutes to complete a goal.Give yourself more than enough time to complete a goal. In recent years, the United States has Group of answer choices had a large goods trade surplus with the rest of the world. exported more services abroad than it has imported. maintained an overall trade surplus (goods and services combined) with the rest of the world. had a small goods trade surplus with Japan A number is more than half of another number by 4. The difference of these two numbers is 2. Find these numbers. If United Airlines acted as a "price leader" and all other airlines simply charged the same prices that United Airlines charged, then could this action be illegal because it is a form of "silent collusion?" A. There is no such term in microeconomics known as "tacit" or "silent collusion." B. Matching the prices of the price leader firm is a good example of a competitive market. C. The U.S. Anti-Trust Department has always considered this business behavior as suspicious and it does consider this pricing strategy to be illegal. D. The famous 1982 anti-monopoly IBM court case said that this pricing strategy within an industry is legal as long as the firms fill out quarterly reports to keep the U.S. Anti-Trust Roselyn is driving to visit her family, which live 150 150150 kilometers away. Her average speed is 60 6060 kilometers per hour. The car's tank has 20 2020 liters of fuel at the beginning of the drive, and its fuel efficiency is 6 66 kilometers per liter. Fuel costs 0.60 0.600, point, 60 dollars per liter. How long can Roselyn drive before she runs out of fuel? A population has a standard deviation of 16. If a sample of size 64 is selected from this population, what is the probability that the sample mean will be within 2 of the population mean? a. Since the mean is not given, there is no answer to this question. b. -0.6826 c. 0.3413 d. 0.6826 e. -0.3413