Answer:
The answer is b=0 or b=9.085603
The equation is solved and the perfect squares are removed from the square root and A = b²√( 30b )
What is an Equation?
Equations are mathematical statements with two algebraic expressions flanking the equals (=) sign on either side.
It demonstrates the equality of the relationship between the expressions printed on the left and right sides.
Coefficients, variables, operators, constants, terms, expressions, and the equal to sign are some of the components of an equation. The "=" sign and terms on both sides must always be present when writing an equation.
Given data ,
Let the equation be represented as A
Now , the value of A is
Substituting the values in the equation , we get
A = √( 30b⁵ )
On simplifying the equation , we get
We can simplify the given expression by breaking down the number inside the square root into its prime factors:
30b⁵ = 2 x 3 x 5 x b⁵
Since we are looking to remove all perfect squares, we can remove the factors of 2 and 3, which are the only perfect squares present in the prime factorization of 30. This leaves us with:
30b⁵ = 2 x 3 x 5 x b⁵
= 2 x 3 x 5 x b⁴ x b
= 30b⁴ x b
Therefore, we can simplify the original expression as:
√(30b⁵) = √(30b⁴ x b) = √(30b⁴) x √b
A = b²√30 x √b
Hence , the expression √(30b⁵) simplifies to A = b²√30 x √b
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Solve the algebraic expressio (0.4)(8)−2
Answer: -6.4
Step-by-step explanation:
(0.4)(8)(-2)
3.2*-2
-6.4
A map's scale is 1 inch : 3.5 miles.
If the distance on the map is
8 inches, then the actual distance
in real life is __miles.
Answer:
28 miles
Step-by-step explanation:
to fin the actual distance you must multiply the didtance on the map by the map scale
3.5*8=28
by which number -7 /25 should be divided to get -1/15?
Answer:
21/5
Step-by-step explanation:
if a/b = c, then b=a/c
in other words:
divide -7/25 by -1/15 to get the answer
It also helps to use the fact that a/b / c/d = a/b * d/c
-7/25 / -1/15 = -7/25 * -15/1
= 105 / 25
= 21 / 5
Answer:
[tex]4 \frac{1}{5} [/tex]
Step-by-step explanation:
[tex] \frac{ - 7}{25} \div x = \frac{ - 1}{15} [/tex]
[tex]x = \frac{ - 7}{25} \div \frac{ - 1}{15} [/tex]
[tex] = \frac{7}{25} \times \frac{15}{1} [/tex]
[tex] = \frac{21}{5} = 4 \frac{1}{5} [/tex]
At noon, ship A is 120 km west of ship B. Ship A is sailing east at 20 km/h and ship B is sailing north at 15 km/h. How fast is the distance between the ships changing at 4:00 PM?
Answer:
1.39 km/h
Step-by-step explanation:
Let the initial position of ship B represent the origin of our coordinate system. Then the position of ship A as a function of time t is ...
A = -120 +20t . . . (east of the origin)
and the position of B is ...
B = 15t . . . (north of the origin)
Then the distance between them is ...
d = √(A² +B²) = √((-120 +20t)² +(15t)²) = √(625t² -4800t +1440)
And the rate of change is ...
d' = (625t -2400)/√(625t² -4800t +14400)
At t = 4, the rate of change is ...
d' = (625·4 -2400)/√(625·16 -4800·4 +14400) = 100/√5200 = 1.39 . . . km/h
The distance between the ships is increasing at about 1.39 km/h.
A child is playing games with empty soda cups. There are three sizes: small, medium, and large. After some experimentation
she discovered she was able to measure out 160 ounces in the following ways:
1) 2 small, 2 medium, 4 large
2) 2 small, 6 medium, 1 large
3) 5 small, 1 medium, 3 large
Determine the size of the cups.
Answer:
S is the volume of the small cup, M the volume of the medium cup and L the volume of the large cup:
2*S + 2*M + 4*L = 160oz
2*S + 6*M + 1*L = 160oz
5*S + 1*M + 3*L = 160oz.
First, we must isolate one of the variables, for this we can use the first two equations and get:
2*S + 2*M + 4*L = 160oz = 2*S + 6*M + 1*L
We can cancel 2*S in both sides:
2*M + 4*L = 6*M + 1*L
now each side must have only one variable:
4*L - 1*L = 6*M - 2*M
3*L = 4*M
L = (4/3)*M.
now we can replace it in the equations and get :
2*S + 2*M + 4*(4/3)*M = 160oz
2*S + 6*M + (4/3)*M = 160oz
5*S + 1*M + 4M = 160oz.
simplifing them we have:
2*S + (22/3)*M + = 160oz
2*S + (22/3)*M = 160oz
5*S + 5*M = 160oz.
(the first and second equation are equal because we used those to get the relation of M and L, so we now have only two equations):
2*S + (22/3)*M = 160oz
5*S + 5*M = 160oz.
We can take the second equation and simplify it:
S + M = 160oz/5 = 32oz
S = 32oz - M
Now we can replace it in the first equation and solve it for M
2*S + (22/3)*M = 2*(32oz - M) + (22/3)*M = 160oz
62oz - 2*M + (22/3)*M = 160oz
-(6/3)*M + (22/3)*M = 98oz
(18/3)*M = 98oz
M = (3/18)*98oz = 16.33 oz
Then:
L = (4/3)*M =(4/3)*16.33oz = 21.78 oz
and:
S = 32oz - M = 32oz - 16.33oz = 15.67oz
It was reported that 23% of U.S. adult cellphone owners called a friend for advice about a purchase while in a store. If a sample of 15 U.S adult cellphone owners is selected, what is the probability that 7 called a friend for advice about a purchase while in a store
Answer:
[tex] P(X=7)[/tex]
And using the probability mass function we got:
[tex]P(X=7)=(15C7)(0.23)^7 (1-0.23)^{15-7}=0.0271[/tex]
Step-by-step explanation:
Let X the random variable of interest, on this case we now that:
[tex]X \sim Binom(n=15, p=0.23)[/tex]
The probability mass function for the Binomial distribution is given as:
[tex]P(X)=(nCx)(p)^x (1-p)^{n-x}[/tex]
Where (nCx) means combinatory and it's given by this formula:
[tex]nCx=\frac{n!}{(n-x)! x!}[/tex]
And we want to find the following probability:
[tex] P(X=7)[/tex]
And using the probability mass function we got:
[tex]P(X=7)=(15C7)(0.23)^7 (1-0.23)^{15-7}=0.0271[/tex]
The three-dimensional figure below is a cylinder with a hole in the shape of a rectangular prism going through the center of it.
The radius is 10 yards. Find the volume of the solid in cubic yards, rounded to the nearest ten. Use 3.14 for pie.
A. 1,980
B. 1,788
C. 1,034
D. 1,884
Answer:
B. 1788
Step-by-step explanation:
The volume of solid shaped is expressed in cubic yards. The sides of the shape are multiplied or powered as 3 for the volume determination. Volume is the total space covered by the object. It includes height, length, width. The three dimensional objects volume is found by
length * height * width
The volume for current object is :
12 * 28 * 5
= 1788 cubic yards.
Answer: 1778
Step-by-step explanation:
because Ik I had the question
Which number is a solution of the inequality: B > 2.1
A: -8
B: -12
C:5
D: 1
Answer:
C. 5 is solution of the inequality: B>2.1
what is the answer pls help me
Answer:
D.
Step-by-step explanation:
It is D. because there are lines on top of the letters meaning that the points PQ, QR, and PR are lines/sides.
You chose the answer already!
What pages will be favored for the given search? Search terms: Michael OR Jordan A. Pages about Michael Jordan B. Pages about Michael, plus pages about OR, plus pages about Jordan C. Pages about Michael, plus pages about Jordan D. Pages about Michael, plus pages about Jordan, plus pages about both
Answer:
A. Pages about Michael Jordan.
Step-by-step explanation:
Michael Jordan, MJ, is a great basketball player, and has achieved one the best records in his career. He is a National Basketball Association (NBA) player with great skills and energy.
From the search item, the two names Michael OR Jordan is for one person, Michael Jordan. The search would combine the two names because it is a well known one and give an output on Michael Jordan. Thus, the pages that would be favored are pages about Michael Jordan.
Scores on the SAT test have a mean of 1518 and a standard deviation of 325. Scores on the ACT test have a mean of 21.1 and a standard deviation of 4.8. Which of the following choices is not true?
A. The ACT score gt 17.0 is relatively better than the SAT score of 1490 a relatively better then the SAT score of 1490 .
B. An SAT score of 1490 has a z-score of -0.09
C. The SAT score of 1490 is relatively better than the ACT score of 17.0.
Answer:
The ACT score gt 17.0 is relatively better than the SAT score of 1490 a relatively better then the SAT score of 1490 .
Step-by-step explanation:
Z-score:
In a set with mean [tex]\mu[/tex] and standard deviation [tex]\sigma[/tex], the zscore of a measure X is given by:
[tex]Z = \frac{X - \mu}{\sigma}[/tex]
The Z-score measures how many standard deviations the measure is from the mean. After finding the Z-score, we look at the z-score table and find the p-value associated with this z-score. This p-value is the probability that the value of the measure is smaller than X, that is, the percentile of X. Subtracting 1 by the pvalue, we get the probability that the value of the measure is greater than X.
A. The ACT score gt 17.0 is relatively better than the SAT score of 1490 a relatively better then the SAT score of 1490.
We find the z-score for each of these options. Whichever has the higher z-score is the better grade.
ACT:
Mean 21.1, standard deviation of 4.8. Score of 17. So [tex]\mu = 21.1, \sigma = 4.8, X = 17[/tex]
[tex]Z = \frac{X - \mu}{\sigma}[/tex]
[tex]Z = \frac{17 - 21.1}{4.8}[/tex]
[tex]Z = -0.85[/tex]
SAT:
Scores on the SAT test have a mean of 1518 and a standard deviation of 325. Score of 1490. So [tex]\mu = 1518, \sigma = 325, X = 1490[/tex]
[tex]Z = \frac{X - \mu}{\sigma}[/tex]
[tex]Z = \frac{1490 - 1518}{325}[/tex]
[tex]Z = -0.09[/tex]
The SAT score of 1490 has the higher z-score, so this is the better score, which means that this statement is false and A. is the answer of this question.
B. An SAT score of 1490 has a z-score of -0.09
From A., this is true
C. The SAT score of 1490 is relatively better than the ACT score of 17.0.
From A., this is true.
volume of a cube size 7cm
Answer:
343 cm3
Step-by-step explanation:
Answer:
side(s) =7cm
volume (v)=l^3
or, v = 7^3
therefore the volume is 343cm^3.
hope its what you are searching for..
Please answer this correctly
Answer:
Option 2
Step-by-step explanation:
The average temperature in January is -1 degrees celsius. Last year, it was 1 degrees celsius higher than the average.
-1 + 1 = 0
Answer:
The second answer.
Step-by-step explanation:
The average temp. is -1C.
'was 1C warmer' = +1
-1+1=0
The completion times for a job task range from 11.1 minutes to 19.2 minutes and are thought to be uniformly distributed. What is the probability that it will require between 14.8 and 16.5 minutes to perform the task?
Answer:
[tex] P(14.8< X<16.5)= \frac{16.5-11.1}{19.2-11.1} -\frac{14.8-11.1}{19.2-11.1}= 0.667-0.457= 0.210[/tex]
The probability that it will require between 14.8 and 16.5 minutes to perform the task is 0.210
Step-by-step explanation:
Let X the random variable "completion times for a job task" , and we know that the distribution for X is given by:
[tex] X \sim Unif (a= 11.1, b= 19.2)[/tex]
And for this case we wantto find the following probability:
[tex] P(14.8< X<16.5)[/tex]
And for this case we can use the cumulative distribution given by:
[tex] F(x) =\frac{x-a}{b-a} , a\leq X \leq b[/tex]
And using this formula we got:
[tex] P(14.8< X<16.5)= \frac{16.5-11.1}{19.2-11.1} -\frac{14.8-11.1}{19.2-11.1}= 0.667-0.457= 0.210[/tex]
The probability that it will require between 14.8 and 16.5 minutes to perform the task is 0.210
Select the correct answer from each drop down menu. AB is dilated by a scale factor of 3 to form A 1 B1. Point O, which lies on AB, is the center of dilation. The slope of AB is 3. The slope of A1 B1 is___. A1 B1 _____ through point O.
Answer:
the slope of A'B' = 3
A'B' passes through point O
Step-by-step explanation:
A dilation with scale factor 3 gives the effect of stretching the line AB three times longer. As dilation does not change the direction of the line, the slope will stay the same. If point O lies on AB and is the center of dilation, then the point O must also lie on A'B'
The required black space in the statement "The slope of AB is 3. The slope of A1 B1 is___. A1 B1 _____ through point O". is filled by 3 and passes.
Given that,
To Select the correct answer from each drop-down menu. AB is dilated by a scale factor of 3 to form A 1 B1. Point O, which lies on AB, is the center of dilation. The slope of AB is 3. The slope of A1 B1 is___. A1 B1 _____ through point O.
The scale factor is defined as the ratio of modified change in length to the original length.
Here, is o is the center of the line AB and slope of line AB is 3 than the line dilated with scale factor 3 A1B1 has also a scale factor of 3 because Position of dilation is center 0 thus dilation did not get any orientation.
And the center of dilation is O so line A1B1 passes through O.
Thus, the required black space in the statement "The slope of AB is 3. The slope of A1 B1 is___. A1 B1 _____ through point O". is filled by 3 and passes.
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Which equation represents the statement below?
Thirteen less than a number is forty-two.
Select one:
a. n – 13 = 42
b. 42 – 13 = n
c. 13 – n = 42
d. 13 – 42 = n
The answer is option A
Step-by-step explanation:
Thirteen less than a number is written as
n - 13
Equate it to 42
We have
n - 13 = 42
Hope this helps you
Pls help with this area question
Answer:
1
Step-by-step explanation:
The lateral area of a cylinder is ...
LA = 2πrh
The total area is that added to the areas of the two circular bases:
A = 2πr² +2πrh
We want the ratio of these to be 1/2:
LA/A = (2πrh)/(2πr² +2πrh) = h/(r+h) = 1/2 . . . . cancel factors of 2πr
Multiplying by 2(r+h) gives ...
2h = r+h
h = r . . . . . subtract h
So, the desired ratio is ...
h/r = h/h = 1
The ratio between height and radius is 1.
A math teacher asks Nico and Katya to solve the following word problem. A car travels 98 miles in 1.7 hours on a freeway where the speed limit is 55 mph. Was the car speeding? Nico and Katya both agree that they should use their calculators to divide the miles by the hours to find the speed of the car, and then compare the answer to 55 mph. However, Nico says it's okay to round what his calculator says to the nearest whole number. Katya says that because the calculator displays eight numbers after the decimal point, they shouldn't round. She says they should write down exactly what the calculator shows. Do you agree with Nico or with Katya? In a short paragraph, explain who you agree with and provide the reasons why.
Answer:
- Was the car speeding?
Yes, the car was speeding as its current speed of 57.65 mph was more than the speed limit of that freeway.
- Do you agree with Nico or with Katya?
I agree somewhat with both Nico and Katya, but, I agree more with Nico.
- Explain your reasoning.
Like I said, I agree more with Nico's method of rounding the speed to the nearest whole number. This is because in this question, the standard speed we want to compare the calculated speed with is given as a whole number. Hence, it is more proper to estimate the calculated speed to its nearest whole number too.
Step-by-step explanation:
Speed during a travel is given as distance travelled divided by time taken
Speed = (Distance/time)
Distance = 98 miles
Time = 1.7 hours
Speed = (98/1.7) = 57.6470588235 = 57.65 mph = 58 mph
- Was the car speeding?
The speed limit for the road is 55 mph and the current speed of the car = 57.65 mph
Since 57.65 > 55
The car was overspeeding.
- Nico says it's okay to round what his calculator says to the nearest whole number. Katya says that because the calculator displays eight numbers after the decimal point, they shouldn't round. She says they should write down exactly what the calculator shows. Do you agree with Nico or with Katya?
I agree somewhat with both Nico and Katya as the both methods of recording the speed ate right, depending on what the speed is required for.
Although, I agree more with Nico's method as it seems like a better fit for the situation described in the question.
- explain who you agree with and provide the reasons why.
Like I said earlier, I agree more with Nico's method of rounding the speed to the nearest whole number. This is because in this question, the standard speed we want to compare the calculated speed with is given as a whole number. Hence, it is more proper to estimate the calculated speed to its nearest whole number too.
Katya's method of writing the calculated speed as is will be correct in cases where extreme accuracy is required, not an estimate. For this question, the estimate will do.
Hope this Helps!!!
Answer:
Yes, the car was speeding as its current speed of 57.65 mph was more than the speed limit of that freeway.
Step-by-step explanation:
Nico and Katya i agree with.
Find the area of a triangle whose two sides are 12 inches and 14 inches long, and has a perimeter of 34 inches.
Answer:
[tex]\huge\boxed{A=3\sqrt{255}\ in^2\approx47.91\ in^2}[/tex]
Step-by-step explanation:
We have two sides
[tex]a=12in;\ b=14in[/tex]
and the preimeter
[tex]P=34in[/tex]
We can calculate the length of the third side:
[tex]c=P-a-b[/tex]
substitute
[tex]c=34-12-14=8\ (in)[/tex]
Use the Heron's formula:
[tex]A=\sqrt{p(p-a)(p-b)(p-c)[/tex]
where
[tex]p=\dfrac{P}{2}[/tex]
substitute:
[tex]p=\dfrac{34}{2}=17\ (in)\\\\A=\sqrt{17(17-12)(17-14)(17-8)}=\sqrt{(17)(5)(3)(9)}\\\\=\sqrt{9}\cdot\sqrt{(17)(5)(3)}=3\sqrt{255}\ (in^2)\approx47.91\ (in^2)[/tex]
given that f(x) = x² + 6x and g(x) = x + 9 calculate
a) f•g (4) =
B) g•f (4) =
Answer:
247
49
Step-by-step explanation:
a) f•g (4) =
f•g (x) = f(g(x)) = (x + 9)^2 + 6(x + 9)
f•g (4) = (4 + 9)^2 + 6(4 + 9)
= 13^2 + 6(13)
= 247
B) g•f (4) =
g•f (x) = g(f(x)) = x^2 + 6x + 9
g•f (4) = 4^2 + 6(4) + 9
= 16 + 24 + 9
= 49
How do you write 0.00609 in scientific notation? ____× 10^_____
Answer:
6.09 * 10 ^-3
Step-by-step explanation:
We want one non zero digit to the left of the decimal
Move the decimal 3 places to the right
6.09
The exponent is 3 and it is negative since we move to the right
6.09 * 10 ^-3
Answer:
6.09(10⁻³)
Step-by-step explanation:
Step 1: Put number into proper scientific decimal form
6.09
Step 2: Figure out how many decimals places it moves
Since it moves to the left 3, our exponent would be -3
There are 7 students in a class: 5 boys and 2 girls.
If the teacher picks a group of 4 at random, what is the probability that everyone in the group is a boy?
Answer:
4/7
Step-by-step explanation:
5+2=7
7 children
4 boys Out of 7 children
Answer:1/7
Step-by-step explanation:
Khan academy
A graph is given to the right. a. Explain why the graph has at least one Euler path. b. Use trial and error or Fleury's Algorithm to find one such path starting at Upper A, with Upper D as the fourth and seventh vertex, and with Upper B as the fifth vertex. A C B D E A graph has 5 vertices labeled A through E and 7 edges. The edges are as follows: Upper A Upper C, Upper A Upper B, Upper A Upper D, Upper C Upper D, Upper C Upper E, Upper B Upper D, Upper D Upper E. a. Choose the correct explanation below. A. It has exactly two odd vertices. Your answer is correct.B. It has exactly two even vertices. C. It has more than two odd vertices. D. All graphs have at least one Euler path. b. Drag the letters representing the vertices given above to form the Euler path.
Answer:
a. It has exactly two odd vertices
b. A C E D B A D C
Step-by-step explanation:
(a) There will not be an Euler path if the number of odd vertices is not 0 or 2. Here, the graph has exactly two odd vertices: A and C.
__
(b) We are required to produce a path of the form {A, _, _, D, B, _, D, _}.
Starting at A, there is only one way to get to node D as the 4th node on the path: via C and E. Node B must follow. From B, there is exactly one way to cover the remaining three edges that have not been traversed so far.
The Euler path meeting the requirements is ...
A C E D B A D C
It is shown by the arrows on the edges in the graph of the attachment.
I NEED HELP PLEASE, THANKS! :)
Answer:
Option D
Step-by-step explanation:
x is given to be 4 in this case, so all we would have to is plug it into the following function -
[tex]f ( x ) = \left \{ {{x - 2, x < 4 } \atop {x + 2, x \geq 4 }} \right[/tex]
Through substitution, you would receive the following function -
[tex]f ( x ) = \left \{ {{2, 4 < 4 } \atop 6, 4 \geq 4 }} \right[/tex]
Now the graph proves that this function is closer to 4, and thus proves that the y - coordinate is about 2 at the same time. However, the graph is cut off, so the limit doesn't exists.
In the diagram below, if AD= 100 and AC = 34, find CD.
A 59
B 76
C 45
D 66
Answer:
D. 66
Step-by-step explanation:
Well if AD is 100 and AC is 34 that leaves CD so we can just subtraction 34 from 100 and get 66.
Answer:
D. 66
Step-by-step explanation:
AD = 100
AC = 34
The whole line is 100. A part of the line is 34. The other part will be 66.
100 - 34 = 66
Express it in slope-intercept form.
A poll found that 5% of teenagers (ages 13 to 17) suffer from arachnophobia and are extremely afraid of spiders. At a summer camp there are 11 teenagers sleeping in each tent. Assume that these 11 teenagers are independent of each other. (Round your answers to four decimal places.)
a) Calculate the probability that at least one of them suffers from arachnophobia. - 0.4312
b) Calculate the probability that exactly 2 of them suffer from arachnophobia? 0.08666
c) Calculate the probability that at most 1 of them suffers from arachnophobia? What is C?
Answer:
a) Calculate the probability that at least one of them suffers from arachnophobia.
x = number of students suffering from arachnophobia
= P(x ≥ 1)
= 1 - P(x = 0)
= 1 - [0.05⁰ x (1 - 0.05)¹¹⁻⁰ ]
= 1 - (0.95)¹¹
= 0.4311999 = 0.4312
b) Calculate the probability that exactly 2 of them suffer from arachnophobia? 0.08666
= P(x = 2)
= (¹¹₂) x (0.05)² x (0.95)⁹
where ¹¹₂ = 11! / (2!9!) = (11 x 10) / (2 x 1) = 55
= 55 x 0.0025 x 0.630249409 = 0.086659293 = 0.0867
c) Calculate the probability that at most 1 of them suffers from arachnophobia?
P(x ≤ 1)
= P(x = 0) + P(x = 1)
= [(¹¹₀) x 0.05⁰ x 0.95¹¹] + [(¹¹₁) x 0.05¹ x 0.95¹⁰]
= (1 x 1 x 0.5688) + (11 x 0.05 x 0.598736939) = 0.5688 + 0.3293 = 0.8981
If a 1/5 of a gallon of paint is needed to cover 1/4 of a wall, how much paint is needed to cover the entire wall
Answer:
4/5 gallon per wall
Step-by-step explanation:
We can find the unit rate
1/5 gallon
------------------
1/4 wall
1/5 ÷ 1/4
Copy dot flip
1/5 * 4/1
4/5 gallon per wall
Answer:
4/5 gallon of paint
Step-by-step explanation:
1/5 gallon of paint is needed to cover 1/4 of the wall.
To cover the whole wall:
1/4 × 4 = 1 (whole)
1/5 × 4 = 4/5
Help me please! I need an answer!
Answer: [tex]\bold{\dfrac{b_1}{b_2}=\dfrac{3}{2}}[/tex]
Step-by-step explanation:
Inversely proportional means a x b = k --> b = k/a
Given that a₁ = 2 --> b₁ = k/2
Given that a₂ = 3 --> b₂ = k/3
[tex]\dfrac{b_1}{b_2}=\dfrac{\frac{k}{2}}{\frac{k}{3}}=\large\boxed{\dfrac{3}{2}}[/tex]
A political candidate has asked you to conduct a poll to determine what percentage of people support her. If the candidate only wants a 4% margin of error at a 99% confidence level, what size of sample is needed? Give your answer in whole people.
Answer:
Step-by-step explanation:
Hello!
The variable of interest is:
X: Number of people that support the candidate.
You need to calculate the sample size to estimate the population proportion of supporters given a confidence level of 99% and a margin of error of 4%
The margin of error of the confidence level for the population proportion is
d= [tex]Z_{1-\alpha /2}[/tex] * [tex]\sqrt{\frac{p'(1-p')}{n} }[/tex]
From this formula you have to clear the value of n:
[tex]\frac{d}{Z_{1-\alpha /2}}[/tex]= [tex]\sqrt{\frac{p'(1-p')}{n} }[/tex]
[tex](\frac{d}{Z_{1-\alpha /2}})^2[/tex]= [tex]\frac{p'(1-p')}{n}[/tex]
[tex]n*(\frac{d}{Z_{1-\alpha /2}})^2[/tex]= [tex]p'(1-p')[/tex]
n= [tex]p'(1-p') * (\frac{Z_{1-\alpha/2}}{d} )^2[/tex]
[tex]Z_{1-\alpha/2}= Z_{0.995}= 2.586[/tex]
sample proportion "p'" since there is no sample information, nor any previous information is known, you have to consider it as the "worse case scenario" and use the value of p'= 0.50
d= 0.04
[tex]n= p'(1-p') * (\frac{Z_{1-\alpha/2}}{d} )^2= 0.5*0.5*(\frac{2.586}{0.04} )^2= 1044.9= 1045[/tex]
She has to take a sample of 1045 people to estimate the population proportion of her supporters with a confidence level of 99% and a margin of error of 4%
I hope this helps!