Area = length x width
Area = 5/6 x 3/4
= (5x3) / (6x4)
= 15/24
= 5/8 square miles
We are interested in finding an estimator for Var (Xi), and propose to use V=-n (1-Xn). 0/2 puntos (calificable) Now, we are interested in the bias of V. Compute: E [V]-Var (Xi)-[n Using this, find an unbiased estimator V for p (1 - p) if n22. rite barX_n for Л n . 72 1--X 7t
Here is the full question .
We are interested in finding an estimator for [tex]Var (X_i )[/tex] and propose to use :
[tex]\hat {V} = \bar {X}_n (1- \bar {X} )_n[/tex]
Now; we are interested in the basis of [tex]\hat V[/tex]
Compute :
[tex]E \ \ [ \bar V] - Var (X_i) =[/tex]
Using this; find an unbiased estimator [tex][ \bar V][/tex] for [tex]p(1-p) \ if \ n \geq 2[/tex]
Write [tex]bar \ x{_n} \ for \ X_n[/tex]
Answer:
Step-by-step explanation:
[tex]\bar X_n = \dfrac{1}{n} {\sum ^n _ {i=1} } \\ \\ E(X_i) = - \dfrac{1}{n=1} \sum p \dfrac{1}{n}*np = \mathbf{p}[/tex]
[tex]V(\bar X_n) = V ( \dfrac{1}{n_{i=1} } \sum ^n \ X_i )} = \dfrac{1}{n^2} \sum ^n_{i=1} Var (X_i) \\ \\ = \dfrac{1}{n^2} \ \sum ^n _{i=1} p(1-p) \\ \\ = \dfrac{1}{n^2}*np(1-p) \\ \\ = \dfrac{p(1-p)}{n}[/tex]
[tex]E( \bar X^2 _ n) = Var (\bar X_n) + [E(\bar X_n)]^2 \\ \\ = \dfrac{p(1-p)}{n}+ p \\ \\ = p^2 + \dfrac{p(1-p)}{n} \\ \\ \\ \hat V = \bar X_n (1- \bar X_n ) = \bar X_n - \bar X_n ^2 \\ \\ E [ \hat V] = E [ \bar X_n - \bar X_n^2] \\ \\ = E[\bar X_n ] - E [\bar X^2_n] \\ \\ = p-(p^2 + \dfrac{p(1-p)}{n}) \\ \\ = p-p^2 -\dfrac{p(1-p)}{n}[/tex]
[tex]=p(1-p)[1-\dfrac{1}{n}] = p(1-p)\dfrac{n-1}{n}[/tex]
[tex]Bias \ (\bar V ) = E ( \hat V) - Var (X_i) \\ \\ = p(1-p) [1-\dfrac{1}{n}] - p(1-p) \\ \\ - \dfrac{p(1-p)}{n}[/tex]
Thus; we have:
[tex]E [\hat V] = p(1-p ) \dfrac{n-1}{n}[/tex]
[tex]E [\dfrac{n}{n-1} \ \ \bar V] = p(1 -p)[/tex]
[tex]E [\dfrac{n}{n-1} \ \ \bar X_n (1- \bar X_n )] = p (1-p)[/tex]
Therefore;
[tex]\hat V ' = \dfrac{n}{n-1} \bar X_n (1- \bar X_n)[/tex]
[tex]\mathbf{ \hat V ' = \dfrac{n \bar X_n (1- \bar X_n)} {n-1}}[/tex]
A hotel rents 220 rooms at a rate of $ 40 per day. For each $ 1 increase in the rate, two fewer rooms are rented. Find the room rate that maximizes daily revenue. The rate that maximizes revenue is $ .
Answer:
The rooms should be rented at $75 per day for a maximum income of $11250 per day.
Step-by-step explanation:
If the daily rental is increased by $ x
then
Rental: R (x )=( 40 + x ) dollars per room-day
Number of rooms rented: N ( x ) = ( 220 − 2 x ) and
Income: I ( x ) = ( 40 + x ) ( 220 − 2 x ) =8800+140x-2x² dollars/day
The maximum will be achieved when the derivative of I ( x ) is zero.
[tex]\frac{dI(x)}{dx} =140-4x=0[/tex]
x=35
so, ($40+$35)=75$per day
I ( x35) =8800+140(35)-2(35)²= 11250
If log10y=2, what does y equal?
Answer:
[tex]y=100[/tex]
Step-by-step explanation:
I don't know if by the 10 you mean the base is 10 or it's being logged with the y, but I'm assuming the base is 10. If that's not right, message me and I'll fix my answer. If,
[tex]log_an=x\\a^x=n[/tex]
Then,
[tex]log_1_0y=2\\10^2=y\\100=y[/tex]
How do you find out part C? Question attached.
Answer:
465 hours
Step-by-step explanation:
Please see attached picture for full solution.
1. substitute the value of A with the surface area of the pond
2. ensure that the coefficient of e is 1.
3. ln both sides
4. bring power down (for left side)
5. ln e= 1
6. find time taken in days
7. change number of days to hours
Please answer this correctly
Answer:
Board Games: 30%
Karaoke: 50%
Bowling: 20%
Step-by-step explanation:
Board Games: [tex]\frac{3}{3+5+2} =\frac{3}{10} =\frac{30}{100}[/tex] or 30%
Karaoke: [tex]\frac{5}{3+5+2} =\frac{5}{10} =\frac{50}{100}[/tex] or 50%
Bowling: [tex]\frac{2}{3+5+2} =\frac{2}{10} =\frac{20}{100}[/tex] or 20%
Answer:
Board Games: 30%
Karaoke: 50%
Bowling: 20%
Step-by-step explanation:
3 + 5 + 2 = 10 so there are 10 family members.
3 out of 10 equals 30%
5 out of 10 equals 50%
2 out of 10 equals 20%
Please mark Brainliest if correct
Hope this helps!
Which ordered pair is the solution of the system of equations? 3x+2y=4, -2+2y=24
Answer:
x = -7.33 OR x = [tex]\frac{-22}{3}[/tex]
y = 13
Step-by-step explanation:
→You can use the substitution method. First, make y by itself in (-2 + 2y = 24):
-2 + 2y = 24
2y = 26
y = 13
→Then, plug in 13 for y into the other equation:
3x + 2y = 4
3x + 2(13) = 4
3x + 26 = 4
3x = -22
x = -7.33 OR x = [tex]\frac{-22}{3}[/tex]
Abena travelled 40% of the distance of her trip alone, went another 35 miles with Saralyn,
and then finished the last half of the journey alone. How many miles long was the journey?
Answer:
350 miles long.
Step-by-step explanation:
First, we analyze the breakdown of the journey
Abena travelled 40% of the distance of her trip alone.She went 35 miles with Saralyn.She finished the last half (50%) of the journey alone.Let the total distance of the journey =x
Therefore:
10% of the total distance of the journey =35 miles
10% of x=35
0.1x=35
Divide both sides by 0.1
x-350 miles
Therefore, the journey was 350 miles long.
Answer:
The journey was 350 miles long
Step-by-step explanation:
The parameters given are;
Distance traveled by Abena alone = 40% and the last half
∴ Distance traveled by Abena alone = 40% + 50% = 90%
Distance Abena traveled with Saralyn = 35 miles = 100% - 90% = 10%
Hence 10% of Abena's journey = 35 miles
The total distance of Abena's journey therefore, is given as follows
10% = 35 miles
Total distance of Abena's journey = 100% of Abena's journey = 10 × 10%
10 × 10% = 10 × 35 miles = 350 miles
The total distance of Abena's journey = 350 miles.
a triangle has an area of 15 cm. a similar triangle is drawn using a scale factor of 3.5. what is the area of the similar triangle to the nearest square cm?
Answer:
184 square cm
Step-by-step explanation:
The ratio of areas is the square of the ratio of the scale factor. The larger triangle has an area of ...
(15 cm²)(3.5²) = 183.75 cm²
The area of the similar triangle is about 184 cm².
Benjamin has 3 gallon of punch he adds another 1/2 gallon of juice to the punch . How many gallons of punch does he have now ? How many cups? Explain
Answer:
3 1/2 gallons or 56 cups
Step-by-step explanation:
1. Analyze the questions.
We have 3 gallons, and we add another 1/2 gallon. This means that our equation must be 3 + 1/2.
2. Solve.
3 + 1/2 = 3 1/2 gallons
3. Convert.
1 gallon = 16 cups
1 * 3 1/2 gallons = 16 * 3 1/2 cups
3 1/2 gallons = 56 cups
Answer: 3 1/2
Hope this helped! :D
So, the question is below, please help me find the answer. :)
Answer:
£2.70 fig rolls and £5.72 crisps
Step-by-step explanation:
£1.08+0.54+£1.08= £2.70 fig rolls
£1.43+£1.43+£1.43-£1.43= £2.86 x 2= £5.72 for 6 packets of crisps
£2.70+ £5.72= £8.42
Thirty percent of all telephones of a certain type are submitted for service while under warranty. Of these, 70% can be repaired, whereas the other 30% must be replaced with new units. If a company purchases ten of these telephones, what is the probability that exactly three will end up being replaced under warranty
Answer:
26.68% probability that exactly three will end up being replaced under warranty
Step-by-step explanation:
For each telephone under warranty, there are only two possible outcomes. Either they need to be replaced, or they do not need to be replaced. Each telephone is independent of other telephones. So we use the binomial probability distribution to solve this question.
Binomial probability distribution
The binomial probability is the probability of exactly x successes on n repeated trials, and X can only have two outcomes.
[tex]P(X = x) = C_{n,x}.p^{x}.(1-p)^{n-x}[/tex]
In which [tex]C_{n,x}[/tex] is the number of different combinations of x objects from a set of n elements, given by the following formula.
[tex]C_{n,x} = \frac{n!}{x!(n-x)!}[/tex]
And p is the probability of X happening.
30% must be replaced with new units
This means that [tex]p = 0.3[/tex]
If a company purchases ten of these telephones, what is the probability that exactly three will end up being replaced under warranty
This is [tex]P(X = 3)[/tex] when [tex]n = 10[/tex]. So
[tex]P(X = x) = C_{n,x}.p^{x}.(1-p)^{n-x}[/tex]
[tex]P(X = 3) = C_{10,3}.(0.3)^{3}.(0.7)^{7} = 0.2668[/tex]
26.68% probability that exactly three will end up being replaced under warranty
DuraBurn claims that the mean lifetime of its SuperGlo light bulbs is 904 hours. A researcher wants to perform a hypothesis test to determine whether the mean lifetime is actually less than this. A random sample of 10 DuraBurn SuperGlo bulbs exhibited an average lifetime x-805 hours with a standard deviation s 158 hours. Using the hypotheses H0: μ = 904 vs Ha: μ < 904, find the P-value and state your conclusion. Use a significance level of 0.05.
1. P-value 0.039, there is not sufficient evidence to conclude the mean lifetime of its SuperGlo light bulbs is less than 904 hours
2. P-value 0.039, there is sufficient evidence to conclude the mean lifetime of its SuperGlo light bulbs is less than 904 hours.
3. P-value 0.079, there is not sufficient evidence to conclude the mean lifetime of its SuperGlo light bulbs is less than 904 hours.
4. P-value0.079, there is sufficient evidence to conclude the mean lifetime of its SuperGlo light bulbs is less than 904 hours
Answer:
Step-by-step explanation:
We would set up the hypothesis test. This is a test of a single population mean since we are dealing with mean
For the null hypothesis,
H0: μ = 904
For the alternative hypothesis,
Ha: μ < 904
This is a left tailed test
Since the number of samples is small and no population standard deviation is given, the distribution is a student's t.
Since n = 10,
Degrees of freedom, df = n - 1 = 10 - 1 = 9
t = (x - µ)/(s/√n)
Where
x = sample mean = 805
µ = population mean = 904
s = samples standard deviation = 158
t = (805 - 904)/(158/√10) = - 1.98
We would determine the p value using the t test calculator. It becomes
p = 0.039
Since alpha, 0.05 > than the p value, 0.03953, then we would reject the null hypothesis. Therefore, the correct option is:
2. P-value 0.039, there is sufficient evidence to conclude the mean lifetime of its SuperGlo light bulbs is less than 904 hours.
-5,-20,-80 find the common ratio
Answer:
The common ratio is 4
Step-by-step explanation:
To find the common ratio take the second term and divide by the first term
-20/-5 = 4
To verify take the third term and divide by the second
-80/-20 = 4
The common ratio is 4
Answer:
4
Step-by-step explanation:
To find the common ratio, divide one term by the term before it.
-20 ÷ -5 = 4
-80 ÷ -20 = 4
Each number is multiplied by 4 to get to the next number.
I hope this helps :))
A study was conducted to determine how bacteria cells multiply over time in a controlled environment. In the study, the bacteria cells were counted once every hour for a total of 6 hours. which one is indepedent variable and dependent varible?
Answer:
Dependent variable → bacteria cell increase or population
Independent variable → time variable
Step-by-step explanation:
An independent variable has direct effect on the dependent variable. The independent variable can stand on it own and it is not change by the other variable you are trying to measure. The independent variable have direct effect on the dependent variable.
A dependent variable is actually the variable being tested in an experiment. The dependent variable is actually dependent on the independent variable.
The dependent variable in this scenario is the bacteria cell increase or the bacteria cell multiplication. The bacteria cell increase is dependent on the time . The time variable is the independent variable as it can stand on it own .
Dependent variable → bacteria cell increase or population
Independent variable → time variable
Determine whether the geometric series 192 + 48 + 12 + ... converges or diverges, and identify the sum if it exists.
A.) Converges: 768
B.) Diverges
C.) Converges; 64
D.) Converges; 256
Answer:
D.) Converges; 256
Step-by-step explanation:
x0= 192
x1 = 48 = 192/4
x2 = 12 = 192/(4 x 4)
Therefore, this series can be written as:
[tex]x_n = \frac{192}{4^n}[/tex]
Applying limits at infinity:
[tex]\lim_{n \to \infty} x_n= \lim_{n \to \infty} (\frac{192}{4^n}) = \frac{192}{\infty}=0[/tex]
Since the terms of the series tend to zero, we can affirm that the series converges.
The sum of an infinite converging series is:
[tex]S=\frac{x_0}{1-r} \\S=\frac{192}{1-\frac{1}{4} }\\S=256[/tex]
Thus, the answer is D.) Converges; 256
Older people often have a hard time finding work. AARP reported on the number of weeks it takes a worker aged 55 plus to find a job. The data on number of weeks spent searching for a job collected by AARP (AARP Bulletin, April 2008) Shows that the mean number of weeks a worker aged 55 plus spent to find a job is 22 weeks. The sample standard deviation is 11.89 weeks and sample size is 40.a) Provide a point estimate of the population mean number of weeks it takes a worker aged 55 plus to find a job.
b) At 95% confidence, what is the margin of error?
c) What is the 95% confidence interval estimate of the mean?
d) Discuss the degree of skewness found in the sample data. What suggestion would you make for a repeat of this study?
Answer:
Step-by-step explanation:
Hello!
Be the variable of interest:
X: Number of weeks it takes a worker aged 55 plus to find a job
Sample average X[bar]= 22 weeks
Sample standard deviation S= 11.89 weeks
Sample size n= 40
a)
The point estimate of the population mean is the sample mean
X[bar]= 22 weeks
It takes on average 22 weeks for a worker aged 55 plus to find a job.
b)
To estimate the population mean using a confidence interval, assuming the variable has a normal distribution is
X[bar] ± [tex]t_{n_1; 1-\alpha /2}[/tex] * [tex]\frac{S}{\sqrt{n} }[/tex]
[tex]t_{n-1; 1-\alpha /2}= t_{39; 0.975}= 2.023[/tex]
The structure of the interval is "point estimate" ± "margin of error"
d= [tex]t_{n_1; 1-\alpha /2}[/tex] * [tex]\frac{S}{\sqrt{n} }[/tex]= 2.023*[tex](\frac{11.89}{\sqrt{40} })[/tex]= 3.803
c)
The interval can be calculated as:
[22 ± 3.803]
[18.197; 25.803]
Using s 95% confidence level, you'd expect the population mean of the time it takes a worker 55 plus to find a job will be within the interval [18.197; 25.803] weeks.
d)
Job Search Time (Weeks)
21 , 14, 51, 16, 17, 14, 16, 12, 48, 0, 27, 17, 32, 24, 12, 10, 52, 21, 26, 14, 13, 24, 19 , 28 , 26 , 26, 10, 21, 44, 36, 22, 39, 17, 17, 10, 19, 16, 22, 5, 22
To study the form of the distribution I've used the raw data to create a histogram of the distribution. See attachment.
As you can see in the histogram the distribution grows gradually and then it falls abruptly. The distribution is right skewed.
Write the standard form of a circle with a center at C(-4, -6) and passes through the point (-1, -2).
Answer:
(x+4)^2+(y+6)^2 = 25
Step-by-step explanation:
The radius squared is equal to the distance between the center and the point
3^2 + 4^2 = 25
We can shift the center like this
(x+4)^2+(y+6)^2 = 25
Daisy has 1/8 tank of gas remaining when she pulls into a gas station. After she puts 15 gallons of gas in her car, the gas gauge reads 3/4 full. How many gallons of gas does Daisy’s tank hold?
*Please Show Work*
Answer:
24
Step-by-step explanation:
Let t represent the volume of the tank in gallons. Then we have ...
(1/8)t + 15 = (3/4)t . . . . . . . . . . . adding 15 gallons fills the tank to 3/4
15 = (6/8 -1/8)t = (5/8)t . . . . . . . subtract 1/8t
15(8/5) = (8/5)(5/8)t . . . . . . . . . multiply by 8/5 (the inverse of 5/8)
24 = t
The tank holds 24 gallons.
Graph the line y=-2x+5
Hope this helps!! :)
Please answer this correctly
Answer:
538
Step-by-step explanation:
l x w
7x39
12x20
5x5
538
Can someone help me?
Answer:
Step-by-step explanation:
a)4a-6a d)2x+4y-10x
=-2a. =-8-+4y
b)14-1-10
=3
c)2+8
=10
e)answer is 6 x raised to the power 3
f)7x raised to the power 2-5x-y
TIVITY MODULE
The length of a rectangle is eight centimeter less than
twice the width. The area of the rectangle is 24
centimeters squared. Determine the dimensions of the
rectangle in centimeters.
Answer: Length: 4, width: 6
Step-by-step explanation:
Let the length be x and width be y
Then x=2y-8 and xy=24
Substitute to get 2y-8 * y = 24, so 2y^2-8y=24 or y^2-4y=12, then solve to get y=6 or y=-2. Since width is positive y=6.
Substitute y=6 into xy=24 to get x=4.
Length: 4, width: 6
Hope that helped,
-sirswagger21
Help me plz
Find the area of the circle use 3.14 for pi
Answer:
530.93 cm thats what i got at least
Answer:
A =530.66 cm^2
Step-by-step explanation:
The area of a circle is given by
A = pi r^2
The radius is given by r =13
A = (3.14) (13)^2
A =530.66 cm^2
Graph g(x), where f(x) = 2x − 5 and g(x) = f(x + 1).
A.) a line labeled g(x) that passes through points 0, negative 4 and 2, 0
B.) a line labeled g(x) that passes through points 0, negative 3 and 4, 5
C.) a line labeled g(x) that passes through points negative 5, negative 3 and 0, 7
D.) a line labeled g(x) that passes through points 0, negative 7 and 5, 3
Answer:
B.) a line labeled g(x) that passes through points 0, negative 3 and 4, 5
Step-by-step explanation:
I graphed both equation on the graph below to find the description of the graph of g(x).
Answer:
b for brakes?
Step-by-step explanation:
I need help with these questions please
Answer:
a) the graph has a minimum
b) (3, 0)
c) x=3
d) N/A
c) (0, 9)
*forgot how to solve for roots
Step-by-step explanation:
Desmos
A trash company is designing an open-top, rectangular container that will have a volume of 1715 ft cubed. The cost of making the bottom of the container is $5 per square foot, and the cost of the sides is $4 per square foot. Find the dimensions of the container that will minimize total cost.
Answer:
14 ft × 14 ft × 8.75 ft
Step-by-step explanation:
A garbage company is designing an open rectangular container that should have a volume of 1,715 cubic feet.
So we have the length of the container = "x" ft, the width of the container = "y" ft and the height of the container = "z" ft
Therefore the volume of the rectangular container would be:
x * y * z = 1715 ft³
z = 1715 / x * y
The cost of making the bottom of the container is $ 5 per square foot, that is:
5 * (x * y)
Now, area of all sides of the container would be:
2 * (x * z + y * z) = 2 * z * (x + y)
We know that it has been given that the cost of making all the sides of the container is = $ 4 per square foot, so:
4 * (2 * z * (x + y)) = 8 * z * (x + y)
In total the costs would be:
5 * (x * y) + 8 * z * (x + y)
If we replace z, in the previous equation we have:
5 * (x * y) + 8 * (1715 / x * y) * (x + y)
solving, and we would have that the total cost would be:
C = 5 * (x * y) + 13720 / x + 13720 / y
Now we will find the derivative of C and make it equal to zero:
dC / dx = 0; dC / dy = 0
For dC / dx = 0:
dC / dx = 5 * y + 13720 * -1 / (y ^ 2) + 13720 * 0
0 = 5 * y - 13720 / y ^ 2
5 * y = 13720 / y ^ 2
y ^ 3 = 13720/5 = 2744
y = 14
For dC / dy = 0:
dC / dy = 5 * x + 13720 * 0 + 13720 * -1 / (x ^ 2)
0 = 5 * x - 13720 / x ^ 2
5 * x = 13720 / x ^ 2
x ^ 3 = 13720/5 = 2744
x = 14
now for z:
z = 1715 / (14 * 14)
z = 8.75
Therefore, the dimensions of the container should be 14 ft × 14 ft × 8.75 ft to minimize manufacturing cost.
Which side will require the use of the distance formula to find the length?
Answer:
CD
Step-by-step explanation:
For all sides except CD, you do not need the distance formula, since they are vertical or horizontal, meaning that you can find their length simply through subtraction. However, with side CD, since it is diagonal, you need to form a right triangle with to solve its length. Hope this helps!
Kortholts that fail to meet certain precise specifications must be reworked on the next day until they are within the desired specifications. A sample of one day's output of kortholts from the Melodic Kortholt Company showed the following frequencies: Plant A Plant B Row Total Specification Met 85 35 120 Specification Not Met 15 25 40 Column Total 100 60 160 Find the chi-square test statistic for a hypothesis of independence. Multiple Choice 7.22 14.22 -0.18 14.70
Answer:
The value of Chi-square test statistic for a hypothesis test of independence is 14.22.
Step-by-step explanation:
The data provided is for one day's output of Kortholt's from the Melodic Kortholt Company.
The formula to compute the chi-square test statistic for a hypothesis of independence is:
[tex]\chi^{2}=\sum {\frac{(O-E)^{2}}{E}}[/tex]
The formula to compute the expected frequencies (E) is:
[tex]E=\frac{\text{Row Total}\times \text{Column Total}}{N}[/tex]
Consider the Excel output attached.
Compute the value of Chi-square test statistic as follows:
[tex]\chi^{2}=\sum {\frac{(O-E)^{2}}{E}}[/tex]
[tex]=1.333+2.222+4.000+6.667\\=14.222\\\approx 14.22[/tex]
Thus, the value of Chi-square test statistic for a hypothesis test of independence is 14.22.
What are the next two numbers in the pattern of numbers 45,15,44,17,40,20,31,25
Answer:
14, 32
Step-by-step explanation:
45,15,44,17,40,20,31,25
this is combination of 2 series:
45-44-40-31- ?15-17-20-25-?In the first series we can see the pattern as:
-1, -4, -9 = -1², -2², -3² so next difference must be -4², which is 31- 16= 14In the second series we can see the pattern as:
2, 3, 5 prime numbers, so next difference must be 7, which is 25+7=32The series will continue as:
45, 15, 44, 17, 40, 20, 31, 25, 14, 32PLEASE HELP QUICKLY AS POSSIBLE THANK YOU :)
Answer:
D (4,11)
Step-by-step explanation:
Answer: it’s d
x is just going up by 1 and y is going up by 2
