Suppose that 3\%3%3, percent of over 200{,}000200,000200, comma, 000 books borrowed from a library in a year are downloaded. The librarians plan to take an SRS of 757575 books from the population of borrowed books to see what proportion of books sampled are downloaded. What are the mean and standard deviation of the sampling distribution of the proportion of downloaded books
Answer:
The mean of the sampling distribution of the proportion of downloaded books is 0.03 and the standard deviation is 0.0197.
Step-by-step explanation:
Central Limit Theorem
For a proportion p in a sample of size n, the sampling distribution of the sample proportion will be approximately normal with mean [tex]\mu = p[/tex] and standard deviation [tex]s = \sqrt{\frac{p(1-p)}{n}}[/tex]
3% of books borrowed from a library in a year are downloaded.
This means that [tex]p = 0.03[/tex]
SRS of 75 books.
This means that [tex]n = 75[/tex]
What are the mean and standard deviation of the sampling distribution of the proportion of downloaded books
By the Central Limit Theorem
Mean: [tex]\mu = p = 0.03[/tex]
Standard deviation: [tex]s = \sqrt{\frac{p(1-p)}{n}} = \sqrt{\frac{0.03*0.97}{75}} = 0.0197[/tex]
The mean of the sampling distribution of the proportion of downloaded books is 0.03 and the standard deviation is 0.0197.
What is the solution to this equation?
x + 14 = -6
Answer:
x = -20
Step-by-step explanation:
A chain of sports shops catering to beginning skiers, headquartered in Aspen, Colorado, plans to conduct a study of how much a beginning skier spends on her initial purchase and supplies. Based on these figures, to explore the possibility of offering combinations, such as a pair ofboots pair skis, induce customers to buy more. As of cash register receipts revealed these initial purchases:$85 $139 $161 $175 $85 $133 $149 $145 $136 131 290235 132 149 322 214 105 90 162 229 121 113 149 126139 118 156 214 172 87 172 230 195 126 128 142 118 139(a) Find the smallest class interval, use five classes.(b) What would be a better class interval?
Answer:
47.4 ;
50
Step-by-step explanation:
Given the data :
X ($) : 85 139 161 175 85 133 149 145 136 131 290 235 132 149 322 214 105 90 162 229 121 113 149 126139 118 156 214 172 87 172 230 195 126 128 142 118 139
The smallest class interval :
Range / number of classes
Number of classes to use = 5
Range = Maximum - Minimum = (322 - 85) =237
Hence, smallest class interval :
237 / 5 = 47.4
A better class interval would be, one without decimal, rounded to the nearest 10; this will be easier and make more statistical sense
Hence, smallest class interval rounded to the nearest 10 :
47.4 = 50 (nearest 10)
Researchers interviewed street prostitutes in Canada and the United States. The mean age of the 100 Canadian prostitutes upon entering prostitution was 19 with a standard deviation of seven. The mean age of the 130 United States prostitutes upon entering prostitution was 21 with a standard deviation of nine. Is the mean age of entering prostitution in Canada lower than the mean age in the United States
Answer:
Step-by-step explanation:
The null and the alternative hypothesis is:
[tex]H_o: \mu_c \ge \mu_{us}[/tex]
[tex]H_a : \mu_c < \mu_{us}[/tex]
The t- student test statistics can be computed as:
[tex]t = \dfrac{x_c- x_{us}}{\sqrt{\dfrac{\sigma_c^2}{n_c} + \dfrac{\sigma_{us}^2}{n_{us}} }}[/tex]
[tex]t = \dfrac{19- 21}{\sqrt{\dfrac{7^2}{100} + \dfrac{8^2}{130} }}[/tex]
t = -2.017
degree of freedom = (n₁ - 1) + (n₂ - 1)
= (100 - 1) + (130 - 1)
= 228
Using the data of t-value and degree of freedom;
The P-value = -0.224
Decision rule: Do not reject the null hypothesis if the p-value is greater than ∝(0.01)
Conclusion: We reject the null hypothesis since the p-value is less than ∝.
Therefore, there is enough evidence to conclude that the mean age of entering prostitution in Canada is lower than that of the United States.
A (3,2) y b (2,-1) pasa por los puntos
=================================
Answer:In the images is the graph of the line that passes through points A (3,2) and B (2, -1)
Also the equation of the line is y = 3x-7
Use two different applications Geogebra and Desmos
================================
RespuestaEn las imágenes está la gráfica de la recta que pasa por los puntos A(3,2) y B(2,-1)
Además, la ecuación de esa recta es y=3x-7
Use dos aplicaciones distintas Geogebra y Desmos
================================
Need help with math points and brainlest
Answer:
22.5 cm
Step-by-step explanation:
Answer:
22.5
Step-by-step explanation:
13.5 / 9 = x / 15
what is the solution to the equation x - 3.9 = 12.4
Answer:
16.8
Step-by-step explanation:
equation: x - 3.9 = 12.9
add 3.9 to 12.9
answer is 16.8
What is the smallest possible value x could take given that it must be an integer?
x>−3
Answer:
The smallest possible value that x could take is -2.
Step-by-step explanation:
Integer values:
Integer values can be either positive or negative, with no decimal parts. The integer set is given by:
{...,-3,-2,-1,0,1,2,3,....}
x>−3
We want the first integer on the number line that is greater than -3. This is -2.
So the smallest possible value that x could take is -2.
Triangle RST has vertices R(-3,2), S(0,-5),and T(4,5).When translated R’ has coordinates (4, 1). Find the coordinates of S’ and T’.
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Lesson 73 - Measuring Volume (C)
QUR
Measuring Volume
E Menu
What is the volume of this rectangular prism?
Enter your answer in the box
in
=lin
2
3
4
5
6
DE 4 ENG
2:06 PM
2/10/2021
A triangle has a base of 4x+2 and a height of x+4. Find the area.
Answer:
15 height
Step-by-step explanation:
Answer:
2x^2 + 9x + 4
Step-by-step explanation:
To find the area of a triangle, use the formula, 1/2 · base · height = area.
If we plug the given expressions into the formula, we get
1/2(4x+2)(x+4)
Which simplifies to
(2x+1)(x+4)
=2x^2 + 9x + 4
police chase a car. police are originally 5 miles behind. if the police car's speed is 90 mph and the car they chase is moving with a speed of 80 mph. how long will it take them to catch up?
Step-by-step explanation:
Let x be the number of hours for
the police to catch up to the car.
We have 90x = 80x + 5.
=> 10x = 5
=> x = 0.5.
Hence it will take them 30 minutes.
Write an
algebraic expression for the situation.
34 divided by a number m
Answer:
34 div 68m??
Step-by-step explanation:
Answer:
answer = 34 / m
Step-by-step explanation:
Usually there would be another number or variable to write an algebraic expression, but if this is the only information given, then this would be the answer
What was Dakota’s height?
Answer:Um her height is 5′ 4″
Step-by-step explanation:
pls help
the answer choices for the first one is.. added , subtracted
the second one is.. added , subtracted
the third one is.. added , subtracted
tysm <3 i’ll mark brainliest
a spider spins a web in the following way it starts at sea level (0)
it moves up one inch in the first minute
it moves down two inches in the second minute
it moves up three inches in the third minute
it moves down four inches in the fourth minute
Assuming that the pattern continues, what will the spiders elevation be after an haour has passed?
Answer:
Step-by-step explanation:
The area of the parallelogram is 315 square units. What is the height of the parallelogram?
Answer:
h = 15 units
Step-by-step explanation:
A = bh
315 = 21h
h = 315/21
h = 15
Answer:
15 sq. units
Step-by-step explanation:
The Intuition for why the area of a parallelogram is A=bh (area = base x height)
The formula for the area of a parallelogram is base times height, just like the formula for the area of a rectangle.
Have a great day!
mayra has $2.95 in nickels and dimes. the number of dimes is 3 less than twice the number of nickels. find the number of nickels.
Answer:
Mayra has 13 nickels
Step-by-step explanation:
Given
Represent dimes with D and nickels with N.
So, from the first statement:
[tex]0.10D + 0.05N = 2.95[/tex]
From the second statement:
[tex]D = 2N - 3[/tex]
Required
Find N
Substitute 2N - 3 for D in [tex]0.10D + 0.05N = 2.95[/tex]
[tex]0.10(2N - 3) + 0.05N = 2.95[/tex]
Open bracket
[tex]0.10*2N - 0.10*3 + 0.05N = 2.95[/tex]
[tex]0.20N - 0.30 + 0.05N = 2.95[/tex]
Collect Like Terms
[tex]0.20N + 0.05N = 2.95+0.30[/tex]
[tex]0.25N = 3.25[/tex]
Make N the subject:
[tex]N = \frac{3.25}{0.25}[/tex]
[tex]N = 13[/tex]
PLEASE HELP IMMEDIATELY!!!
Lavilla is a famous resort in Italy. All of its rooms are always booked in the winter season. On average, 2800 skiers come to the resort every week (7 days). On average, skiers stay in Lavilla for 4 days. Each skier spends $40 daily in local restaurants. Question 1 (1 point) The average number of skiers in Lavilla is: _____________ [skiers].
Answer:
The average number of skiers in Lavilla are 1,600 skiers
Step-by-step explanation:
The number of skiers that come to Lavilla on average each week = 2,800 skiers
The number of days each skier stays in Lavilla = 4 days
The amount each skier spends in local restaurants daily = $40
According to Little's Law, we have;
L = λ·W
Where;
L = The average number of skiers in Lavilla
λ = The effective arrival rate of the skiers = 2,800 skiers per week arrive
W = The number of days each skier stays at Lavilla = 4 days = 4/7 week
The average number of skiers in Lavilla, 'L', is therefore, given as follows;
L = 2,800 skiers/weel × (4/7) week = 1,600 skiers
The average number of skiers in Lavilla, L = 1,600 skiers
8x – 3y = -21
y = 5x + 7
Which statements for 63.372 are true? Check all that are true. The digit 2 is in the thousandths place. The digit 7 is in the hundredths place. The digit 7 is in the thousandths place. The digit 3 is in the tenths place. The digit 2 is in the tenths place. please help with this question
Answer:
sorry
Step-by-step explanation:
sana i review mo beh ng maayos..hehe wag puro tanong cge keep safe..
pls help my brainly buddies
Answer:
≈ 41.2°Step-by-step explanation:
Given ΔABD with:
AC⊥BDBC = 6 cmBD = 22 cmArea(ABC) = 42 cm²Find ∠D = xConsider ΔABC
Area = 1/2BC*AC42 = 1/2*6*ACAC = 42/3 = 14Consider ΔACD
CD = BD - BC = 22 - 6 = 16 cmAC = 14 cmtan x = AC/CDtan x = 14/16 = 0.875x = arctan 0.875x ≈ 41.2°Answer:
≈ 41.2°
Step-by-step explanation:
The ratio of tomatoes to pepper plants in the garden is 5:2. If there are 6 more tomato plants than pepper plants, how many pepper plants are in the garden?
The ratio from tomatoes to pepper plants is 5:2
Meaning there are 5 tomatoes and 2 pepper plants
In order to find a ratio where there are 6 more tomatoes than pepper plants you will have to multiply.
-----
When the ratio 5:2 is multiplied by 2
it equals 10:4
We can stop here because it is shown that now there are 6 more tomatoes than pepper plants.
-----
So there are:
10 tomatoes
and
4 pepper plants!
Find the lcd between 1/6 and 2/9. Show your work.
Working alone, it takes Stephanie seven hours to clean an attic. Shayna can clean it in 12 hours. How long would it take them to clean the attic working together?
Mhanifa please help!! I will mark brainliest. Random answers will be reported
Answer:
[tex]\sqrt{h^2 + k^2}[/tex]Step-by-step explanation:
Point O has coordinates (0, 0) B has coordinates (h, k)C has coordinates (h, 0)Use the distance formula to find the length of OB:
OB = [tex]\sqrt{(h-0)^2 + (k-0)^2}[/tex] = [tex]\sqrt{h^2 + k^2}[/tex]Find the missing length indicated. Leave your answer in simplest radical form.
Answer:
18[tex]\sqrt{3}[/tex]
Step-by-step explanation:
The hypotenuse of the 45-45-90 triangle is [tex]\sqrt{2}(9\sqrt{2} ) = 18[/tex]
The hypotenuse of the 45-45-90 triangle is also the shorter leg of the
30-60-90 triangle
The longer leg = x = shorter leg times [tex]\sqrt{3\\}[/tex] = 18[tex]\sqrt{3\\}[/tex]
Select the words that are spelled correctly.
angal
chuckle
barral
sandal
woolen
listan
Questions:
1. If the run of a ramp increases and the rise stays the same, how does the slope of the ramp change?
9514 1404 393
Answer:
slope decreases
Step-by-step explanation:
The slope of a ramp is directly proportional to the rise and inversely proportional to the run. When the run increases, the slope decreases.
