Answer:
here you go!
The U.S. Department of Agriculture records data on farm acreage and number of farms by county for every county in the country. This takes considerable time and energy, and the results for each update (usually occurring approximately every five years) are a long time in process. A quicker way to update the data is by sampling. The table below shows the number of counties in each geographic region and a summary of farm acres (in thousands) for independent random samples of 22 counties from each region.
Region Number of counties
North Central 1052
North East 210
South 1376
West 418
Required:
a. Estimate the mean acreage for each region, with a margin of error.
b. Estimate the total acreage for each region, with a margin of error.
c. Estimate the difference between mean acreage for the North Central region and the South, with a margin of error.
d. Estimate the difference between mean acreage for the North East and the West, with a margin of error.
e. Estimate the mean acreage per county across the United States, with a margin of error.
Solution :
From the table,
Number of countries = [tex]$N_i$[/tex]
Mean = [tex]$\overline Y_i$[/tex]
Standard deviation = [tex]$\sigma_i$[/tex]
Margin of error of B = 50,000 acres
So we determine the [tex]$\text{sample size n}$[/tex] and then allocate the four regions of [tex]$n_1, n_2, n_3$[/tex] and [tex]$n_4$[/tex].
Under the [tex]$\text{proportional allocation}$[/tex], the [tex]$\text{equation}$[/tex] for the value of [tex]$n_1$[/tex] which yields [tex]$V(\overline Y_{st}) = D = \frac{B^2}{H}$[/tex] is given by :
[tex]$n=\frac{\sum_{K=1}^L N_K \sigma^2_K}{ND+\frac{1}{N}\sum_{K=1}^L N_K \sigma^2_K}$[/tex]
Let us complete the numerator
[tex]$\sum_{K=1}^L N_K \sigma^2_K = N_1\sigma_1^2 + N_2\sigma_2^2 + N_3\sigma_3^2 + N_4\sigma_4^2$[/tex]
[tex]$= 1052 \times (271)^2 + 210 \times (79)^2 + 1376 \times (244)^2 + 418 \times (837)^2 $[/tex]
= 453329920
The bound on the error of estimation is B = 50,000 acres
Hence we get
[tex]$D=\frac{B^2}{H}$[/tex]
[tex]$=\frac{50000^2}{4}$[/tex]
= 625,000,000
[tex]$n=\frac{\sum_{K=1}^L N_K \sigma^2_K}{ND+\frac{1}{N}\sum_{K=1}^L N_K \sigma^2_K}$[/tex]
[tex]$=\frac{453329920}{3056 \times 625 + \frac{1}{3056} \times 453329920}$[/tex]
= 220.24044
≈ 221 (approximately)
Therefore, the sample size under the proportional allocation from each stratum are given by :
[tex]$n_1=n\left[\frac{N_1}{\sum_{K=1}^\mu N_K}\right]$[/tex]
[tex]$=221\left[\frac{1052}{3056}\right]$[/tex]
≈ 76
[tex]$n_2=n\left[\frac{N_2}{\sum_{K=1}^\mu N_K}\right]$[/tex]
[tex]$=221\left[\frac{210}{3056}\right]$[/tex]
≈ 15
[tex]$n_3=n\left[\frac{N_3}{\sum_{K=1}^\mu N_K}\right]$[/tex]
[tex]$=221\left[\frac{1376}{3056}\right]$[/tex]
≈ 100
[tex]$n_4=n\left[\frac{N_4}{\sum_{K=1}^\mu N_K}\right]$[/tex]
[tex]$=221\left[\frac{418}{3056}\right]$[/tex]
≈ 30
Thus, we should select 76 counties from North central region, 15 counties from the north east region, 100 from south region and 30 from west region.
We can also estimate mean acreage of each county across all the county with a margin of error of 50,000 acres.
Two boats started to move towards each other from two docks, located 30 miles apart. One boat moved at a speed of 3 miles per hour, the other moved twice as fast. How soon will the boats meet?
Answer:
3.333 hours
Step-by-step explanation:
Given the total distance is 30 miles, and boat 1 travels at 3 mph and boat 2 travels at 6 mph, and the time for both is the same. Distance is speed S times time T so
30 = D(boat 1) + D(boat 2)
30 = (S1 * T) + (S2 * T)
30 = 3T + 6T
30 = 9T
3.333 = T
The histogram shows the ages of the players in an adult volleyball league. Which of the
following statements is true?
Volleyboll Players Ages
The older the age group, the greater the
number of players
5
There are 30 players between ages 20 and 25.
Number of Players
More than half of the players are under age
40.
20% 30% 50's 70's
Age Group
There must be 5 players between 50 and 55.
Answer:
More than half of the players are under age
40.
Step-by-step explanation:
Evaluating the expression : More than half of the players are under age 40.
Below 40s :
Number of players in 20s = 19
Number of players in 30s = 24
(19 + 24) = 43 players
40s and above :
40s = 8 players
50s = 10 players
60s = 5 players
70s = 2 players
(8 + 10 + 5 + 2) = 25 players
Hence, total number of players below 30s is more Than half of the total players
Directions: Encircle the letter of the correct answer.
1. What do you call the distance around a cirde?
A. area
B. perimeter
C. circumference
volume
2. Jenny made a circular veil has a radius of 4 decimeters. How many decimeters of lace
trimmings were needed to put around the veil?
A. 8 decimeters
B. 16 decimeters
C. 12 decimeters
D. 25.12 decimeters
3. The circular based statue in the middle of a fountain City Hall Park has a diameter of 9
meters. If the City Mayor would like to put decorative ribbon around it, how much ribbon is
needed?
A. 18 meters
B. 28.26 meters
C. 27 meters
D. 81 meters
4. Mr. Cruz planted santan in his circular garden with a diameter of 8 meter. What is the
circumference of his garden?
A. 16 meters
B. 25.12 meters
C. 24 meters
D. 64 meters
5. Robert's mother is making a pot holder with a diameter of 7 meters. How many meters of
lace she needs to decorate around the pot holder?
A. 14 meters
B. 21.98 meters
C. 21 meters
D. 49 meters
Answer:
Step-by-step explanation:
1.C. circumference
2.D. 25.12 decimeters
Solution
C=2πr=2·π·4≈25.13274
3.B. 28.26 meters
Using the formulas
C=2πr
d=2r
Solving for C
C=πd=π·9≈28.27433m
4.B. 25.12 meters
Using the formulas
C=2πr
d=2r
Solving for C
C=πd=π·8≈25.13274m
5.B. 21.98 meters
Using the formulas
C=2πr
d=2r
Solving for C
C=πd=π·7≈21.99115m
An accessories store sells $8 custom socks and $11 custom hats. If 11 items were sold on Monday, and the
total sales were $100, how many socks were sold?
Answer:
7 socks were sold
Step-by-step explanation:
7*8=56
11-7=4
4×11=44
56+44=100
This proves the answer of 7 to be correct
-61=-3(1-5p)+4(-8-7p)
Answer: hello! have a good day! :)))
P = 2
PLEASE HELP ME IT'S MY LAST GRADE
Answer:
c
Step-by-step explanation:
Answer:
C
Step-by-step explanation:
Eight new graduates are hired by an engineering firm. Each is assigned at random to one of eight cubicles arranged in a row in the back of the room that houses the engineering staff. Two of the graduates are Bill and Cathy. What is the probability that they are assigned adjacent cubicles
Answer:
the probability that they are assigned adjacent cubicles is 1 ÷ 4
Step-by-step explanation:
Given that
There is 8 new graduates are hired
2 of the graduates are bill and cathy
And, each one is assigned on random basis
We need to find out the probability
So,
= (2) (7!) ÷ (8!)
= (2) ÷ (8)
= 1 ÷ 4
Hence, the probability that they are assigned adjacent cubicles is 1 ÷ 4
The same would be relevant
which of the following represents the equality for the sum of 11 and Y is greater than -33
Answer:
11+y > -33
Step-by-step explanation:
Answer:
You wrote
"Which of the following" Meaning there's should be options present.
But Going with the statement...
The sum of 11 and y is greater than -33
I'd say
11 + y > -33.
please help
thank you
Answer:
Step-by-step explanation:
-4<n≤5
What is the area of the polygon?
Answer:
[tex]154m^{2}[/tex]
Step-by-step explanation:
8 · 7 = 56m (horizontal rectangle shape) the width was given by subtracting the total of the width (23m) minus (16m).
5 · 8 = 40m (square shape) Subtract 8m - 3m = 5m.
6 · 8 = 48m (square shape to the left of the polygon)
2 · 5 = 10m (small rectangle shape bottom left) 8 - 6 = 2 for the length and 5 for the width by 8 - 3 = 5
56m + 40m + 48m + 10m = 154 [tex]m^{2}[/tex]
SOMEONE HELP ME WITH THIS PLEASE IM STRUGGLING
Answer:
Final point (-4, 4) Original point (3, -4)
Answer:
Again, I can't move it for you but I can give you the points!
original: (3, -4)
final: (-4, 4)
The ratio of red chairs to blue chairs in the cafeteria is 3:5. If there are a total of 144 chairs in the cafeteria, how many are red?
Answer:
54.
Step-by-step explanation:
The fraction that are red = 3/(3+5) = 3/8.
So number of red chairs = 3 * 144/8
= 54.
Which of the following is the point and slope of the equation y + 2 = 2(x - 8)?
-8, 2), 2
(2, -8), 2
(8, -2), 2
(-2, 8), 2
There are eight boys and seven girls in a class. The teacher randomly selects three different students to answer questions. What is the probability that the first two students are girls followed by a boy?
the probability is 7/15
Step-by-step explanation:
because there are 7 girls and 8 boys
Ica ingin membuat sebuah lampion
berbentuk kubus, panjang rusuknya 15
dm, maka volume lampion Ica adalah
... m?
a. 45
b. 3,375
c. 33,75
d. 3,375
Well the answer is 3,375
Which expression is NOT equal to 28?
A (9 + 25 = 5) x 2
B. [(13 – 4x2) – 1] x 7
C. 42 = 6 + 28 = 4
D. 7 [8 - (12 - 4x 2)]

Answer:
aaaaa
Step-by-step explanation:
Answer:
I think it’s A
Step-by-step explanation:
which number line shows the solution to the inequality below
-4g<4
(look at picture)
Answer:
b
Step-by-step explanation:
make g by itself -> inequality becomes g>-1. Answer choice b fits the criteria
Estimate the line of best fit using two points on the line. (8, 80) 100 90 80 70 60 50 40 30 20 10 (2.20) 10 O A. y= 2x O B. y = 2x + 10 O c. y= 10x+ 2 OD. y= 10x
Answer:
[tex]y = 10x[/tex]
Step-by-step explanation:
Given
The attached plot
Required
The line of the best fit using [tex](8,80)[/tex] and [tex](2,20)[/tex]
We have:
[tex](x_1,y_1) = (8,80)[/tex]
[tex](x_2,y_2) = (2,20)[/tex]
Calculate slope (m)
[tex]m = \frac{y_2 - y_1}{x_2 - x_1}[/tex]
[tex]m = \frac{20 - 80}{2- 8}[/tex]
[tex]m = \frac{-60}{-6}[/tex]
[tex]m = 10[/tex]
The equation is then calculated using:
[tex]y = m(x - x_1) + y_1[/tex]
[tex]y = 10(x - 8) + 80[/tex]
Expand
[tex]y = 10x - 80 + 80[/tex]
[tex]y = 10x[/tex]
Seventy of Jo’s students are traveling by bus to the aquarium. They rented 2 buses, but there were only 64 seats. The remaining 6 students had to travel in a van. The equation 2b+6=70 represents the given scenario. What does B represent?
A. The number of students who rode on each bus
B. The number of buses
C. The total number of students going to The football game
D. The number of vans
Answer:
A
Step-by-step explanation:
Is 5pi/3 the same as 5/3 radians?
Best answer gets brainliest!!
using power to a power, what is (3^3)^3*
19,683
Hope this Helped!
If you place a 35-foot ladder against the top of a 31-foot building, how many feet will the bottom of the ladder be from the bottom of the building? Round to the nearest tenth of a foot.
Answer:
4ft
Step-by-step explanation:
The bottom of the ladder will be 16.25 feet from the bottom of the building.
What is the right triangle?A right triangle is defined as a triangle in which one angle is a right angle or two sides are perpendicular.
As per the situation, we create a right triangle as shown.
Let x be the distance from the bottom of the building to the bottom of the ladder.
Using Pythagoras's theorem, then, we have:
x² + 31² = 35²
Simplifying this equation, we get:
x² = 35² - 31²
x² = 264
x = 16.25 (rounded to the nearest tenth of a foot).
Therefore, the bottom of the ladder will be 16.25 feet from the bottom of the building.
Learn more about Pythagoras's theorem here:
brainly.com/question/343682
#SPJ6
Find the value of the following by suitable rearrangement. Mention the
property used.
a. 25 x 679 x 4
b. 2917 x 102 - 2917 x 2
(a) 67900
(b) 291700
Step-by-step explanation:(a) 25 x 679 x 4
Rearrange the terms starting with the smallest
4 x 25 x 679
The property used here is the commutative property of multiplication which states that the order in which these numbers are multiplied does not matter.
Now solve
4 x 25 x 679 = 67900
(b) 2917 x 102 - 2917 x 2
Factor out the common terms
2917(102 - 2)
Using the distributive property which states that when a number is multiplied by the sum or difference of two numbers, the result is the same as multiplying each of the two numbers by the number and then adding or subtracting the products.
Now solve
2917(102 - 2) = 2917(100)
= 291700
Two angles are complementary. mZT is (3x + 17)° and mZW is 19°
Solve for x and for mZT.
Answer:
x = 18
mZT = 71º
Step-by-step explanation:
Complementary angles total 90º
(3x + 17) + 19 = 90
Subtract 19 from both sides
3x + 17 = 71
mZT = 71º
Subtract 17 from both sides
3x = 54
Divide both sides by 3
x = 18
Plz help me well mark brainliest if you are correct!..
Answer:
8
Step-by-step explanation:
all numbers must be positive when you have the lines on the side
Answer:
8
Step-by-step explanation:
Give the trigonometric form of each vector (leave the magnitude as a square root) p=
(<2V6, -2V2)
Answer:
[tex]v=<\sqrt{32}cos(319.11^{\circ}),\sqrt{32}sin(319.11^{\circ})>[/tex] or [tex]v=\sqrt{32}cos(319.11^{\circ})i+\sqrt{32}sin(319.11^{\circ})j[/tex]
Step-by-step explanation:
Find the magnitude of [tex]<2\sqrt{6},-2\sqrt{2}>[/tex]:
[tex]||v||=\sqrt{(2\sqrt{6})^2+(-2\sqrt{2})^2}[/tex]
[tex]||v||=\sqrt{24+8}[/tex]
[tex]||v||=\sqrt{32}[/tex]
Find the direction angle of [tex]<2\sqrt{6},-2\sqrt{2}>[/tex]:
[tex]\alpha=tan^{-1}|\frac{-2\sqrt{2}}{2\sqrt{6}}|[/tex]
[tex]\alpha=tan^{-1}|-\frac{\sqrt{3}}{2}|[/tex]
[tex]\alpha=tan^{-1}(\frac{\sqrt{3}}{2})[/tex]
[tex]\alpha=40.89^{\circ}[/tex]
Since [tex]\alpha=40.89^{\circ}[/tex] is our reference angle, we determine our direction angle [tex]\theta[/tex] by verifying our angle is in Quadrant IV, which is where the vector is located. Therefore, [tex]\theta=360^{\circ}-\alpha=360^{\circ}-40.89^{\circ}=319.11^{\circ}[/tex]
To represent a vector's magnitude and direction in trigonometric form, we use the form [tex]v=<||v||cos\theta,||v||sin\theta>[/tex] or [tex]v=||v||cos\theta i+||v||sin\theta j[/tex].
In conclusion, the trigonometric form of the vector is:
[tex]v=<\sqrt{32}cos(319.11^{\circ}),\sqrt{32}sin(319.11^{\circ})>[/tex] or
[tex]v=\sqrt{32}cos(319.11^{\circ})i+\sqrt{32}sin(319.11^{\circ})j[/tex]
Q 16 Two numbers are in the ratio 3 : 17. If the first is 6, what is the other?
Ops: A.
w
O 51
B.
O 68
C.
0 42
5723
D.
O 34
Answer:
D 34
Step-by-step explanation:
i hope you understand
how do you find 25% of 92
Answer:
23
Step-by-step explanation:
suzanne babysits to earn extra money. she charges $15 for each hour that she babysits. What represents the independent variable in this situation?
A. The total amount charged for babysitting
B. The rate she us paid per hour
C. The number of hours she babysits
D. The number of children she babysits
Answer:
C. The number of hours she babysits
Step-by-step explanation:
In this situation, the number of hours she babysits is the independent variable.
This is because it will directly influence the amount of money that she earns, which is the dependent variable.
For example, working for 1 hour will earn her $15.
So, the correct answer is C. The number of hours she babysits