Answer:
5%
Step-by-step explanation:
There are 2000000 people out of town and 4000000 people in total.
Solution for 2000000 is what percent of 40000000:
2000000:40000000*100 =
(2000000*100):40000000 =
200000000:40000000 = 5
Now we have: 2000000 is what percent of 40000000 = 5
Question: 2000000 is what percent of 40000000?
Percentage solution with steps:
Step 1: We make the assumption that 40000000 is 100% since it is our output value.
Step 2: We next represent the value we seek with x
Step 3: From step 1, it follows that 100%= 40000000.
Step 4: In the same vein, x%=2000000.
Step 5: This gives us a pair of simple equations:
100%=40000000(1).
x%=2000000(2).
Step 6: By simply dividing equation 1 by equation 2 and taking note of the fact that both the LHS
(left hand side) of both equations have the same unit (%); we have
100%/x%=40000000/2000000
Step 7: Taking the inverse (or reciprocal) of both sides.
⇒ x=5%
Therefore, 2000000 is 5% of 40000000.
I hope that answers your question and plz mark me brainliest!
how many whole numbers are there between 40 and 75
Answer:
2
Step-by-step explanation:
50 and 60
Answer: 35 whole numbers.
Step-by-step explanation:
You could just find the difference between the numbers or list the numbers.
75-40=35
Or, 41,42,43,44,45,46,46,47,48,49,50,51,52,53,54,55,56,57,58,59,60,61,62,63,64,65,66,67,68,69,70,71,72,73,74.
All these numbers are whole numbers between 40 and 75 and they all count up to 35.
You plan to conduct a marketing experiment in which students are to taste one of two different brands of soft drink. Their task is to correctly identify the brand tasted. You select a random sample of 200 students and assume that the students have no ability to distinguish between the two brands. (Hint: if an individual has no ability to distinguish between the two soft drinks, then each brand is equally likely to be selected.)(a) What is the probability that the sample will have between 50% and 60% of the identification correct?(b) The probability is 90% that the sample percentage contained within what symmetrical limits of the population percentage?(c) What is the probability that the sample percentage of correct identifications is greater than 65%?
Answer:
a) probability that the sample will have between 50% and 60% of the identification correct = 0.498
b) The probability is 90% that the sample percentage is contained 45.5% and 54.5% of the population percentage
c) Probability that the sample percentage of correct identifications is greater than 65% = 0.01
Step-by-step explanation:
Sample size, n = 200
Since the brands are equally likely, p = 0.5, q = 0.5
The Standard deviation, [tex]\sigma_p = \sqrt{\frac{pq}{n} }[/tex]
[tex]\sigma_p = \sqrt{\frac{0.5 * 0.5}{200} } \\\sigma_p = 0.0353[/tex]
a) probability that the sample will have between 50% and 60% of the identification correct.
[tex]P(0.5 < X < 0.6) = P(\frac{0.5 - 0.5}{0.0353} < Z < \frac{0.6 - 0.5}{0.0353} )\\P(0.5 < X < 0.6) = P( 0 < Z < 2.832)\\P(0.5 < X < 0.6) = P(Z < 2.832) - P(Z < 0)\\P(0.5 < X < 0.6) = 0.998 - 0.5\\P(0.5 < X < 0.6) = 0.498[/tex]
Probability that the sample will have between 50% and 60% of the identification correct is 0.498
b) p = 90% = 0.9
Getting the z value using excel:
z = (=NORMSINV(0.9) )
z = 1.281552 = 1.28 ( 2 dp)
Then we can calculate the symmetric limits of the population percentage as follows:
[tex]z = \frac{X - \mu}{\sigma_p}[/tex]
[tex]-1.28 = \frac{X_1 - 0.5}{0.0353} \\-1.28 * 0.0353 = X_1 - 0.5\\-0.045+ 0.5 = X_1\\X_1 = 0.455[/tex]
[tex]1.28 = \frac{X_2 - 0.5}{0.0353} \\1.28 * 0.0353 = X_2 - 0.5\\0.045+ 0.5 = X_2\\X_2 = 0.545[/tex]
The probability is 90% that the sample percentage is contained 45.5% and 54.5% of the population percentage
c) Probability that the sample percentage of correct identifications is greater than 65%
P(X>0.65) = 1 - P(X<0.65)
[tex]P(X<0.65) = P(Z< \frac{X - \mu}{\sigma} )\\P(X<0.65) = P(Z< \frac{0.65 - 0.5}{0.0353} )\\P(X<0.65) = P(Z < 4.2372) = 0.99\\P(X>0.65) = 1 - P(X<0.65)\\P(X>0.65) = 1 - 0.99\\P(X>0.65) = 0.01[/tex]
A study reports that college students work, on average, between 4.63 and 12.63 hours a week, with confidence coefficient .95. Which of the following statements are correct?MARK ALL THAT ARE TRUE.There are four correct answers. You must mark them all to get credit.A. The interval was produced by a technique that captures mu 95% of the time. B. 95% of all college students work between 4.63 and 12.63 hours a week. C. 95% of all samples will have x-bar between 4.63 and 12.63. D. The probability that mu is between 4.63 and 12.63 is .95. E. 95% of samples will produce intervals that contain mu. F. The probability that mu is included in a 95% CI is 0.95. G. We are 95% confident that the population mean time that college students work is between 4.63 and 12.63 hours a week.
Answer:
Step-by-step explanation:
Confidence coefficient is also the confidence level. A confidence coefficient of 0.95 is the same as a confidence level of 95%.
Confidence level is used to express how confident we are that the population mean lies within the calculated confidence interval. It expresses the possibility of getting the same result if tests are repeated. Since the study reports that college students work, on average, between 4.63 and 12.63 hours a week, with confidence coefficient .95, then the true statement is
G. We are 95% confident that the population mean time that college students work is between 4.63 and 12.63 hours a week.
Suppose that theta is an angle in standard position whose terminal side Intersects the unit circle at (-11/61, -60/61)
Find the exact values of tan theta, sec theta, and cos theta.
Answer:
The exact values of the tangent, secant and cosine of angle theta are, respectively:
[tex]\cos \theta = -\frac{11}{61}[/tex]
[tex]\tan \theta = \frac{-\frac{60}{61} }{-\frac{11}{61} } = \frac{60}{11}[/tex]
[tex]\sec \theta = \frac{1}{-\frac{11}{61} } = -\frac{61}{11}[/tex]
Step-by-step explanation:
The components of the unit vector are [tex]x = -\frac{11}{61}[/tex] and [tex]y = -\frac{60}{61}[/tex]. Since [tex]r = 1[/tex], then [tex]x = \cos \theta[/tex] and [tex]y = \sin \theta[/tex]. By Trigonometry, tangent and secant can be calculated by the following expressions:
[tex]\tan \theta = \frac{\sin \theta}{\cos \theta} = \frac{y}{x}[/tex]
[tex]\sec \theta = \frac{1}{\cos \theta} = \frac{1}{x}[/tex]
Now, the exact values of the tangent, secant and cosine of angle theta are, respectively:
[tex]\cos \theta = -\frac{11}{61}[/tex]
[tex]\tan \theta = \frac{-\frac{60}{61} }{-\frac{11}{61} } = \frac{60}{11}[/tex]
[tex]\sec \theta = \frac{1}{-\frac{11}{61} } = -\frac{61}{11}[/tex]
Round 0.043118 to 1 significant figure.
Answer:0.04
Step-by-step explanation:numbers from 0-4 are rounded off while numbers from 5-9 are rounded up by adding 1 to the number before. Significant number are numbers from 1above
Therefore 0.043118 to 1 significant number is 0.04
The number 0.043118 rounded to 1 significant figure is given by the equation A = 0.04
What is rounding up numbers?There are basically two rules while rounding up numbers
If the number you are rounding is followed by 0, 1, 2, 3, or 4, round the number down and if the number you are rounding is followed by 5, 6, 7, 8, or 9, round the number up.
Non-zero digits are always significant
Zeros between non-zero digits are always significant
Leading zeros are never significant
Trailing zeros are only significant if the number contains a decimal point
Given data ,
Let the number be represented as n
The value of n = 0.043118
Let the rounded number be represented as A
So , when rounding the number to one significant number , the leading zeros are never significant and non-zero digits are always significant
Substituting the values in the equation , we get
A = 0.04
Hence , the rounded number is 0.04
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All equilateral triangles are also isosceles triangles.
Answer:
True
Step-by-step explanation:
Isosceles triangles are a subset of equilateral triangles
Equilateral have all three sides the same while isosceles have at least 2 sides the same
Equilateral have all three angles equal while isosceles have at least 2 angles equal
Answer:
Yes
Step-by-step explanation:
An equilateral triangle is one where all three sides are of equal length. (3)
An isosceles triangle has at least two sides of equal length. (2)
But, if it's the other way around than no
You spin a spinner that has 15 equal-sized sections numbered 1 to 15. Find the theoretical probability of: P(odd number)
Answer: The correct answer is
Step-by-step explanation:
The probability of P(odd number) for odd numbers is 8/15
What is probability?Probability is a branch of mathematics that deals with the occurrence of a random event. For example, when a coin is tossed in the air, the possible outcomes are Head and Tail.
According to question
A spinner that has 15 equal-sized sections numbered 1 to 15.
Total number of selection = 15
therefore odd no's are = 1,3,5,7,9,11,13,15 in total 8
And even no's are = 2,4,6,8,10,12,14 in total 7
Now probability of: P(odd number) = [tex]\frac{Total odd no's }{Total number of selection}[/tex]
= 8/15
Hence, the probability of odd number is 8/15
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The difference between an ostrich's speed and a chicken's speed
is 31 miles per hour. An ostrich can run at a speed of 40 miles
per hour. Use mental math or the guess, check, and revise strategy
to solve the equation 40 – c= 31 to find c, the speed a chicken
can run.
Answer:
9 miles an hour
Step-by-step explanation:
9
Ben's employer will reimburse him $0.13 per mile driven. If Ben drives 210.1 miles on a business trip, what is his mileage reimbursement?
Answer:
27.31
Step-by-step explanation:
Take the number of miles and multiply by the reimbursement rate
210.1 * .13
27.313
Round to the nearest cent
27.31
Evaluate cos0 if sin0= 5/3
Answer:
cos0 = 4/3
Step-by-step explanation:
If sin0 = 5/3 then cos0 = 4/3
Sin is opposite/hypotenuse or 5/3.
Cos is adjacent/hypotenuse or 4/3
I found 4 because of Pythagorean Theorem on the triangle, which is known as a 345 triangle.
What is the mean of the following set of data?
{4,3,1, 6, 1,7}
Answer:
3.6666666.... and continuing
or 3.7 if you want to round
Step-by-step explanation:
To find the mean, I added all the numbers up:
4+3+1+ 6+ 1+7 = 22
Then I divided that by how many numbers there are total (6).
22/6= 3.66666.. or 3.6 with a bar symbol on top of the 6.
Thus, the answer is 3.666666...
Suppose that Motorola uses the normal distribution to determine the probability of defects and the number of defects in a particular production process. Assume that the production process manufactures items with a mean weight of 10 ounces. Calculate the probability of a defect and the suspected number of defects for a 1,000-unit production run in the following situations.
(a) The process standard deviation is 0.15, and the process control is set at plus or minus one standard deviation. Units with weights less than 9.85 or greater than 10.15 ounces will be classified as defects. If required, round your answer to four decimal places.
(b) Through process design improvements, the process standard deviation can be reduced to 0.05. Assume that the process control remains the same, with weights less than 9.85 or greater than 10.15 ounces being classified as defects. If required, round your answer to four decimal places.
(c) What is the advantage of reducing process variation, thereby causing process control limits to be at a greater number of standard deviations from the mean?
Answer:
[tex]\mathbf{P(X < 9.85 \ or \ X> 10.15) \approx 0.3171}[/tex] to four decimal places.
[tex]\mathbf{P(X < 9.85 \ or \ X> 10.15) =0.0027}[/tex] to four decimal places.
Step-by-step explanation:
a)
Assuming X to be the random variable which replace the amount of defectives and follows standard normal distribution whose mean (μ) is 10 ounces and standard deviation (σ) is 0.15
The values of the random variable differ from mean by ± 1 \such that the values are either greater than (10+ 0.15) or less than (10-0.15)
= 10.15 or 9.85.
The probability that the amount of defectives which are either greater than 10.15 or less than 9.85 can be calculated as follows:
[tex]P(X < 9.85 \ or \ X> 10.15) = 1-P ( \dfrac{9.85-10}{0.15}< \dfrac{X-10}{0.15}< \dfrac{10.15-10}{0.15})[/tex]
[tex]P(X < 9.85 \ or \ X> 10.15) = 1- \phi (1) - \phi (-1)[/tex]
Using the Excel Formula ( = NORMDIST (1) ) to calculate for the value of z =1 and -1 ;we have: 0.841345 and 0.158655 respectively
[tex]P(X < 9.85 \ or \ X> 10.15) = 1- (0.841345-0.158655)[/tex]
[tex]P(X < 9.85 \ or \ X> 10.15) =0.31731[/tex]
[tex]\mathbf{P(X < 9.85 \ or \ X> 10.15) \approx 0.3171}[/tex] to four decimal places.
b) Through process design improvements, the process standard deviation can be reduced to 0.05.
The probability that the amount of defectives which are either greater than 10.15 or less than 9.85 can be calculated as follows:
[tex]P(X < 9.85 \ or \ X> 10.15) = 1-P ( \dfrac{9.85-10}{0.05}< \dfrac{X-10}{0.05}< \dfrac{10.15-10}{0.05})[/tex]
[tex]P(X < 9.85 \ or \ X> 10.15) = 1- \phi (3) - \phi (-3)[/tex]
Using the Excel Formula ( = NORMDIST (3) ) to calculate for the value of z =3 and -3 ;we have: 0.99865 and 0.00135 respectively
[tex]P(X < 9.85 \ or \ X> 10.15) = 1- (0.99865-0.00135)[/tex]
[tex]\mathbf{P(X < 9.85 \ or \ X> 10.15) =0.0027}[/tex] to four decimal places.
(c) What is the advantage of reducing process variation, thereby causing process control limits to be at a greater number of standard deviations from the mean?
The main advantage of reducing the process variation is that the chance of getting the defecting item will be reduced as we can see from the reduction which takes place from a to b from above.
Can someone please answer this quick!
It is recommended that one smoke detector be installed for every 500 square feet of floor area in a building. Write an equation to determine s, the number of smoke detectors needed for a building with 7,250 Square feet of floor space.
How many smoke detectors are needed for that building?
Answer:
Equation- 7,250 divided by 500
Answer- 15
Step-by-step explanation:
thanks google for letting me look this up! ;)
Answer:
s = 7,250/500
Step-by-step explanation:
If you want a smoke detector every 500 feet you divide the total amount (7,250) into (s) many 500 foot spaces. This means that you could also divide 7,250 by 500 ft to get s or the number of smoke detectors needed.
Give the numerical value of the parameter p in the following binomial distribution scenario.
The probability of winning an arcade game is 0.632 and the probability of losing is 0.368. If you play the arcade game 10 times, we want to know the probability of winning no more than 8 times.
Consider winning as a success in the binomial distribution. Do not include p= in your answer.
Answer:0.9306
Step-by-step explanation:
Given
Probability of winning [tex]p=0.632[/tex]
Probability of losing [tex]q=0.368[/tex]
Such that [tex]p+q=1[/tex]
Applying binomioal distribution for n=10 trials
Probability of winning no more than 8 time=P
[tex]P(r\leq 8)+P(r>8)=1[/tex]
[tex]P(r\leq 8)=1-P(r>8)[/tex]
[tex]P(r\leq 8)=1-^{10}C_9(p)^9(q)-^{10}C_{10}(p)^{10}(q)^0[/tex]
[tex]P(r\leq 8)=1-^{10}C_9(0.632)^9(0.368)-^{10}C_{10}(0.632)^{10}(0.368)^0[/tex]
[tex]P=P(r\leq 8)=0.9306[/tex]
N
2) A sample of size n= 49 is obtained. The population mean
is m= 80 and the population standard deviation is s = 14.
Find the probability that the sample has a sample average
between 78.3 and 85.1, (5 points)
-
Answer:
0.7969
Step-by-step explanation:
Given that: A sample of size n= 49 is obtained. The population mean is m= 80 and the population standard deviation is s = 14.
The z score measures the number of standard deviation by which the raw sore is above or below the mean. It is given by the equation:
[tex]z=\frac{x-m}{\frac{s}{\sqrt{n} } }[/tex]
For x = 78.3, the z score is:
[tex]z=\frac{x-m}{\frac{s}{\sqrt{n} } }=\frac{78.3-80}{\frac{14}{\sqrt{49} } } =-0.85[/tex]
For x = 85.1, the z score is:
[tex]z=\frac{x-m}{\frac{s}{\sqrt{n} } }=\frac{85.1-80}{\frac{14}{\sqrt{49} } } =2.55[/tex]
P(78.3<x<85.1) = P(-0.85<z<2.55) = P(z<2.55) - P(z<-0.85) = 0.9946 - 0.1977 = 0.7969
Answer:
P(78.3 < x' < 85.1) = 0.7969
Step-by-step explanation:
Given:
Sample size, n = 49
mean, u = 80
Standard deviation [tex] \sigma [/tex] = 14
Sample mean, ux' = population mean = 80
Let's find the sample standard deviation using the formula:
[tex] \sigma \bar x = \frac{\sigma}{\sqrt{n}} [/tex]
[tex] = \frac{14}{\sqrt{49}} = \frac{14}{7} = 2 [/tex]
To find the probability that the sample has a sample average between 78.3 and 85.1, we have:
[tex] P(78.3 < \bar x < 85.1) = \frac{P[(78.3 -80)}{2} < \frac{(\bar x - u \bar x)}{\sigma \bar x} < \frac{(85.1 -80)}{2}] [/tex]
= P( -0.85 < Z < 2.55 )
= P(Z < 2.55) - P(Z <-0.85 )
Using the standard normal table, we have:
= 0.9946 - 0.1977 = 0.7969
Approximately 0.80
Therefore, the probability that the sample has a sample average between 78.3 and 85.1 is 0.7969
The average cost of tuition, room and board at small private liberal arts colleges is reported to be $8,500 per term, but a financial administrator believes that the average cost is higher. A study conducted using 350 small liberal arts colleges showed that the average cost per term is $8,745. The population standard deviation is $1,200. Let ? = 0.05
What is the test statistic for this test?
Answer:
The test statistic for this test is 3.82.
Step-by-step explanation:
The null hypothesis is:
[tex]H_{0} = 8500[/tex]
The alternate hypotesis is:
[tex]H_{1} > 8500[/tex]
Our test statistic is:
[tex]t = \frac{X - \mu}{\frac{\sigma}{\sqrt{n}}}[/tex]
In which X is the sample mean, [tex]\mu[/tex] is the value tested at the null hypothesis, [tex]\sigma[/tex] is the standard deviation of the population and n is the size of the sample.
In this question:
[tex]X = 8745, \mu = 8500, \sigma = 1200, n = 350[/tex]
So
[tex]t = \frac{8745 - 8500}{\frac{1200}{\sqrt{350}}} = 3.82[/tex]
The test statistic for this test is 3.82.
Evaluate the numerical expression.
9 × [(25 − 6) − (6 + 5)]
Answer:
72
Step-by-step explanation:
9 * (19 - 11)
= 9 * 8 = 72
Insect Weights Consider a dataset giving the adult weight of species of insects. Most species of insects weigh less than 5 grams, but there are a few species that weigh a great deal, including the largest insect known: the rare and endangered Giant Weta from New Zealand, which can weigh as much as 71 grams. Is the shape of the distribution symmetric, skewed to the right, or skewed to the left
Answer:
Step-by-step explanation:
71 grams would definitely be an outlier on the high side, whereas "most" species would weigh much less. Thus, the graph of this distribution of weights would be skewed towards the lower side, that is, to the left.
The skewness of a dataset is a measure of deviation of a random variable from the normal distribution.
The shape of the distribution is skewed to the right
From the question, we understand that:
Most of the species are less than 5 grams.One specie weighs 71 grams71 is a very large dataset, compared to the other weight of the species.
This means that
71 is an outlier of the dataset.The dataset is concentrated at the left (less than 5)When there are much data at the left of a distribution, then the distribution is positively skewed.
Hence, the shape of the is skewed to the right
See attachment for illustration of skewness of a distribution.
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These prisms have different shapes as end faces
Triangle (3 sides) 5 9 6
Rectangle (4 sides) 6 12 8
Pentagon (5 sides) 7 15 10
Hexagon (6 sides) 8 18 12
b) 300 edges and 200 vertices
(a) The complete table describes a number of faces, edges, and vertices shown below.
(b) There are 300 edges and 200 vertices in a prism with a 100-sided end face
In the given figure one is a triangular prism and the lower one is a pentagonal prism. With the help of the figure, we have to calculate the complete table and the number of edges and vertices a prism with a 100-sided end face has.
(a)
The complete table is given as:
Triangle (3 sides) 5 9 6
Rectangle (4 sides) 6 12 8
Pentagon (5 sides) 7 15 10
Hexagon (6 sides) 8 18 12
(b)
The number of vertices in a prism is determined by the number of vertices on its base polygon. Therefore, there are 300 edges and 200 vertices in a prism with a 100-sided end face.
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There are 232 people waiting in line for
an amusement park ride. Each car on
the ride will be filled with 5 people.
How many cars are needed to hold all
the people waiting in line?
TRY IT
Answer:
232 ÷ 5 = 46.4
you will need 47 cars.
If a number ends in zero, then it is divisible by five
Answer:
Yes
Step-by-step explanation:
10,20,30,40,50 are all divisible by 5.
What is the inverse of the function G(X)=-2(x-4)
Answer:
Step-by-step explanation:
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The inverse of the function G(X)=-2(x-4) is G'(x) = -(1/2)x +4
What is a Function?A function is a law that relates a dependent and an independent variable.
The function is g(x) = -2(x-4)
The inverse of a function is found by interchanging the position of the x an d y variable and then solving for y in terms of x.
g(x) = -2 (x-4)
y = -2(x-4)
Interchanging y to x
x = -2( y-4)
x = -2y +8
(x - 8)/ -2 = y
y = 4 - (1/2)x
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What is 5 square root28 plus square root 63 in simplest radical form
Answer:
13√7
Step-by-step explanation:
[tex]5\sqrt{28} +\sqrt{63} =5\sqrt{2^2\cdot 7}+\sqrt{3^2\cdot 7}\\\\=5\cdot 2\sqrt{7}+3\sqrt{7}=(10+3)\sqrt{7}\\\\=\boxed{13\sqrt{7}}[/tex]
Write an equation for "nine times a number decreased by five is the same as six times the same number increased by seven.
Answer: 9*x-5 = 6*x+7
Step-by-step explanation:
First we have to understand what it is saying.
9 times x (being a number) minus 5 equal to 6 times x plus 7
Now lets put it into an equation.
[tex]9*x-5 = 6*x+7[/tex]
What is the amplitude ? How do I find it? do I add -3.8 to 3.8 then divide? Thank you in advance
Answer:
7.6subtract the midline from the peak valueStep-by-step explanation:
The amplitude is the difference between the peak value (3.8) and the midline (-3.8). You find it by subtracting the midline from the peak:
amplitude = 3.8 -(-3.8)
amplitude = 7.6
at noon a train leaves Washington DC headed for Charleston South Carolina a distance of 500 Miles the train traveling at a speed of 44 miles at 1 p.m. a second train leaves Charleston heading for Washington DC traveling 32 miles an hour how long after the train view Charleston where the trains pass each other
At a car rental agency, 0.39 of the cars are returned on time. A sample of 12 car rentals is studied. What is the probability that more than 3 of them are returned on time?
Answer:
Probabilty of more than 3 =0.8474
Step-by-step explanation:
Probabilty of returned on time P= 0.39
Probabilty of not on time q=1-0.39= 0.61
Sample = 12 cars
Selected items = 3 cars
Probabilty of3 returned on time
= 12C3 * (0.39)^3 * (0.61)^9
= 220*(0.059319)*(0.011694146)
= 0.1526
Note**** C represents combination
So probability of more than 3 means greater than 3 = from 4 above
Probability of more than 3 = 1-probability of three
Probabilty of more than 3 = 1-0.1526
Probabilty of more than 3 =0.8474
A researcher wishes to estimate the percentage of adults who support abolishing the penny. What size sample should be obtained if he wishes the estimate to be within 3 percentage points with 95% confidence if
(a) he uses a previous estimate of 32%?
(b) he does not use any prior estimates?
Answer:
a) [tex]n=\frac{0.32(1-0.32)}{(\frac{0.03}{1.96})^2}=928.81[/tex]
And rounded up we have that n=929
b) [tex]n=\frac{0.5(1-0.5)}{(\frac{0.03}{1.96})^2}=1067.11[/tex]
And rounded up we have that n=1068
Step-by-step explanation:
Part a
The margin of error for the proportion interval is given by this formula:
[tex] ME=z_{\alpha/2}\sqrt{\frac{\hat p (1-\hat p)}{n}}[/tex] (a)
And on this case we have that [tex]ME =\pm 0.03[/tex] and we are interested in order to find the value of n, if we solve n from equation (a) we got:
[tex]n=\frac{\hat p (1-\hat p)}{(\frac{ME}{z})^2}[/tex] (b)
For a confidence of 95% we have that the significance is [tex]\alpha=0.05[/tex] and the critical value would be:
[tex] z = 1.96[/tex]
And replacing into equation (b) the values from part a we got:
[tex]n=\frac{0.32(1-0.32)}{(\frac{0.03}{1.96})^2}=928.81[/tex]
And rounded up we have that n=929
Part b
For this case since we don't have prior info we can use as estimator for the true proportion the value [tex]\hat p=0.5[/tex] and replacing we got:
[tex]n=\frac{0.5(1-0.5)}{(\frac{0.03}{1.96})^2}=1067.11[/tex]
And rounded up we have that n=1068
Michael puts 21 sports cards into stacks of 3. The answer is 7. What’s the question?
c^2 = a^2 + b^2 - 2ab cos C make cos C the subject of the formula
Answer:
[tex]\frac{c^{2}-a^{2}-b^{2} }{-2ab}[/tex]=cos C
Step-by-step explanation:
Start with the parts that are more loosely attached to the cos C: the a² and the b², they are only attached with addition, which can be easily undone by subtracting from both sides. That gives you c²-a²-b²=-2abC
Next, since you want to isolate cosC, you will want to divide by everything attached to the cosC by multiplication: (c²-a²-b²)÷(-2ab)=cosC. Then you can neaten it up and put it in fraction form: [tex]\frac{c^{2}-a^{2}-b^{2} }{-2ab}[/tex]=cos C
