Answer:
5.3 days
Step-by-step explanation:
Let us assume the loss of ability to recall a learned material = 100%
Formula to calculate number of days = time(t) =
t = t½ × Log½(Nt/No)
Nt = Ending Amount
No = Beginning Amount
t½ = Half life
t = Time elapsed
Therefore, we have the following values from the questions:
Half life (t½)= 35 days
Initial or beginning amount = 100%
Ending amount = 90%
t = t½ × Log½ (Nt/No)
t = 35 × Log ½(90/100)
t = 5.3201082705768 days
Approximately = 5.3 days
A news article estimated that only 5% of those age 65 and older who prefer to watch the news, rather than to read or listen, watch the news online. This estimate was based on a survey of a large sample of adult Americans. Consider the population consisting of all adult Americans age 65 and older who prefer to watch the news, and suppose that for this population the actual proportion who prefer to watch online is 0.05. A random sample of n = 100 people will be selected from this population and p, the proportion of people who prefer to watch online, will be calculated.
(a) What are the mean and standard deviation of the sampling distribution of p? (Round your standard deviation to four decimal places.
(b) Is the sampling distribution of p approximately normal for random samples of size n 100? Explain.
i. The sampling distribution of p is approximately normal because np is less than 10.
ii. The sampling distribution of p is approximately normal because np is at least 10.
iii. The sampling distribution of p is not approximately normal because np is less than 10
iv. The sampling distribution of p is not approximately normal because np is at least 10
v. The sampling distribution of p is not approximately normal because n(1 - p) is less than 10.
(c) Suppose that the sample size is n = 400 rather than n = 100, what are the values for the mean and standard deviation when n=400?
Does the change in sample size affect the mean and standard deviation of the sampling distribution of p? If not, explain why not.
i. When the sample size increases, the mean increases.
ii. When the sample size increases, the mean decreases.
iii. When the sample size increases, the mean stays the same.
iv. The sampling distribution is always centered at the population mean, regardless of sample size.
v. When the sample size increases, the standard deviation increases.
vi. When the sample size increases, the standard deviation decreases.
Answer:
3.25
Step-by-step explanation:
In the figure below, angle y and angle x form vertical angles. Angle x forms a straight line with the 50° angle and the 40° angle. A straight line is shown and is marked with three angles. The first angle measures 50 degrees. The second angle measures 60 degrees. The third angle is labeled x. The line between the 40 degree angle and angle x extends below the straight line. The angle formed is labeled angle y. Write and solve an equation to determine the measure of angle y.
Step-by-step explanation:
sorry but u should provide with a diagram for better understanding of ur question
These box plots show daily low temperatures for a sample of days in two different towns.
A
---------------------------------------------------------
Answer: I just took the test and it is D
4 Which object has the shape of a
rectangular prism?
O pencil
O book
O scissors
A segment with endpoints at $A(2, -2)$ and $B(14, 4)$ is extended through $B$ to point $C$. If $BC = \frac{1}{3} \cdot AB$, what are the coordinates for point $C$? Express your answer as an ordered pair.
Answer:
C = (18, 6)
Step-by-step explanation:
You have ...
AB : BC = 1 : 1/3 = 3 : 1
(B -A) / (C -B) = 3/1 . . . . . another way to write the distance relation
B -A = 3(C -B) . . . . . . . . . multiply by (C-B)
4B -A = 3C . . . . . . . . . . . add 3B
C = (4B -A)/3 . . . . . . . . . divide by 3 to get an expression for C
C = (4(14, 4) -(2, -2))/3 = (54, 18)/3
C = (18, 6)
Suppose we randomly selected 250 people, and on the basis of their responses to a survey we assigned them to one of two groups: high-risk group and low-risk group. We then recorded the blood pressure for the members of each group. Such data are called
Answer:
Matched or paired data
Step-by-step explanation:
In statistics the different types of study included experimental and observational with the matched or paired data.
The observational study is one in which there is no alteration in the obseravtions or any change. It is purely based on observations.
The experimental study is one in which some experiment or change is brought about to see the effects of the experiment and the results are recorded as before and after treatment etc.
The matched or paired study is one in which two or more groups are simultaneously observed , recorded to find the difference between them or other parameters which maybe useful for the differences or similarities.
What is the lateral area of the drawing is it a 200 km.b. 425.c.114d.1021km
Answer:
114 km
Step-by-step explanation:
Each side is an isosceles trapezoid, so ED=2 since you would need to add 2 to each end of the bottom line to get the top line. Now use Pythagorean Theorem to get ED^2+AD^2=AE^2. Plug in your numbers to solve for AE. This is the height of each trapezoid. Then use your formula for the area of a trapezoid, (B1+B2)h/2, to get the area of each side, then multiply by 4 to get the lateral area since there are 4 sides. Remember lateral area is just the sides, then surface area is when you include the area of the two bases.
Find X using the Angle Sum Theorem
Answer:
x = 20°
Step-by-step explanation:
So when I learned it we called it the exterior angle theorem not the angle sum theorem but here goes.
Since exterior angle = 110 Degrees,
--> The Inner 2 angles's sum = 110 Degrees
so, 70 + 2x = 110
=> 2x = 40
x = 20
x = 20°
Hope this helps!
i need help really bad
Answer:
see explanation
Step-by-step explanation:
If f(x) and [tex]f^{-1}[/tex] are inverse functions, then
f([tex]f^{-1}[/tex])(x) = x
Thus substitute x = [tex]f^{-1}[/tex] (x) into f(x)
f([tex]\frac{x+6}{5}[/tex] )
= 5 ([tex]\frac{x+6}{5}[/tex] ) - 6
= x + 6 - 6
= x
Thus f(x) and [tex]f^{-1}[/tex] (x) are inverse functions
ASAP Which graph has a correlation coefficient, r, closest to 0.75?
Answer:
C. Graph C
Step-by-step explanation:
In a scatter plot, a positive correlation coefficient suggests that as one variable increases the other increases as well, or as one decreases, the other decreases.
Also, the more clustered the data points are along the line of best fit, the higher the value of the coefficient, whether positive or negative.
Graph C shows a positive correlation because as the variable on the x-axis increases, the variable on the y-axis also increases. The data points are more clustered along the line if best fit, if we draw one. This suggest a positive correlation coefficient (r) as strong as 0.75.
Graph C has a correlation coefficient, r, that is closer to 0.75.
Answer: graph A ‼️
Step-by-step explanation:
Fresno County, California is the largest agricultural producing county in the country and almonds are an important crop with more than 99,000 acres harvested. Each acre produces about a ton of almonds and sold at a price of $4300 a ton. The Sagardia Brothers grew 600 acres of almonds . How many tons would the brothers sell if they priced the almonds at $4500 a ton?
Answer:
0 ton
Step-by-step explanation:
The question states that 99,000 acres are harvested. This suggest that there are plenty sellers of almonds.The Sagardia Brothers grew 600 acres of almonds. this is a small percentage of the total output of almonds. This suggests that the market for almonds is perfectly competitive.
In this type of market, if the price of a seller is above equilibrium price, zero units of the commodity would be bought. This is because the goods sold are homogenous and buyers can easily purchase from other buyers that sell at the market price
X = y + 12
How to solve for variable
Answer:
x-y=12
Step-by-step explanation:
Was it evaluated correctly?
Explain your reasoning
help i need to turn it in a hour
Answer:
no
Step-by-step explanation:
2(4+10)+20
2(14)+20
28+20
48
What is the distance between the coordinates (4,2) and (0,2)
Answer: Hi!
The distance between the coordinates (4,2) and (0,2) is 4 units.
The coordinates have the same location on the y axis, but the coordinates have different locations on the x axis. (4,2) is 4 units to the right of the x axis and 2 up on the y axis, while (0,2) goes just straight up to 2 on the y axis. If we graphed these, the two points would be aligned with each other, but a distance of 4 units would separate them horizontally.
Hope this helps!
The sum of two numbers is 15. One number is 101 less than the other. Find the numbers.
Answer:
The numbers:
-43 and 58
Step-by-step explanation:
a + b = 15
a = b - 101
then:
(b-101) + b = 15
2b = 15+101
2b = 116
b = 116/2
b = 58
a = b - 101
a = 58 - 101
a = -43
Check:
a + b = 15
-43 + 58 = 15
simplify use the multiplication rule
Answer:
3
Step-by-step explanation:
[tex] \sqrt[4] {27} \cdot \sqrt[4] {3} = [/tex]
[tex] = \sqrt[4] {27 \cdot 3} [/tex]
[tex] = \sqrt[4] {3^3 \cdot 3^1} [/tex]
[tex] = \sqrt[4] {3^4} [/tex]
[tex] = 3 [/tex]
In order to purchase a new backyard patio in 3 years, the Robinsons have decided to deposit $1,700 in an account that earns 6% per year compounded monthly for 3 years. How much money will be in the account in 3 years?
Answer: A = 2,034.356 ≈ $2,034.36
$2,034.36 will be in the account in 3 years
Step-by-step explanation:
Given that ;
P = $1,700
Rate r = 6%
Time period (t) = 3 years
now to find how much money will be in the account in 3 years
we say;
A = P ( 1 + r/n )^nt
A = 1,700 ( 1 + 0.06/12) ¹²ˣ³
A = 1,700 ( 1.19668)
A = 2,034.356 ≈ $2,034.36
v divided by 5 is equal to 60.
Answer:
[tex]\boxed{v=300}[/tex]
Step-by-step explanation:
Hey there!
To find v we’ll set up the following,
v ÷ 5 = 60
To get v by itself we’ll do
5*60 = 300
v = 300
Hope this helps :)
An arithmetic sequence has this recursive formula: (a^1 =8, a^n= a^n-1 -6
A.a^n=8+(n-6)(-1)
B.a^n=8+(n-1)(-6)
C.
Answer:
[tex]a_n = 8 + (n - 1) (-6)[/tex]
Step-by-step explanation:
Given
[tex]a_1 = 8[/tex]
Recursive: [tex]a_{n} = a_{n-1} - 6[/tex]
Required
Determine the formula
Substitute 2 for n to determine [tex]a_2[/tex]
[tex]a_{2} = a_{2-1} - 6[/tex]
[tex]a_{2} = a_{1} - 6[/tex]
Substitute [tex]a_1 = 8[/tex]
[tex]a_2 = 8 - 6[/tex]
[tex]a_2 = 2[/tex]
Next is to determine the common difference, d;
[tex]d = a_2 - a_1[/tex]
[tex]d = 2 - 8[/tex]
[tex]d = -6[/tex]
The nth term of an arithmetic sequence is calculated as
[tex]a_n = a_1 + (n - 1)d[/tex]
Substitute [tex]a_1 = 8[/tex] and [tex]d = -6[/tex]
[tex]a_n = a_1 + (n - 1)d[/tex]
[tex]a_n = 8 + (n - 1) (-6)[/tex]
Hence, the nth term of the sequence can be calculated using[tex]a_n = 8 + (n - 1) (-6)[/tex]
The number of weekly hours spent on a smart device varies inversely with the person's age. If a 20-year-old person spends 52 hours on their smart device each week, how many hours does a 50-year-old person spend on their smart device?
Answer:
20.8 hours
Step-by-step explanation:
Given that hours (h) varies inversely with age (a) then the equation relating them is
h = [tex]\frac{k}{a}[/tex] ← k is the constant of variation
To find k use the condition h = 52 when a = 20, thus
52 = [tex]\frac{k}{20}[/tex] ( multiply both sides by 20 )
1040 = k
h = [tex]\frac{1040}{a}[/tex] ← equation of variation
When a = 50, then
h = [tex]\frac{1040}{50}[/tex] = 20.8 hours
In a frequency distribution of 290 scores, the mean is 99 and the median is 86. One would expect this distribution to be:
Answer:
positively skewed to the right
Step-by-step explanation:
The measure of the central tendency is a profound way to describe the mean, median and mode. The measure of central tendency indicates where the center of distribution tends to be. The measure of central tendency provide a validity and answers whether the scores are high or generally low.
In this measure,The mean is usually pulled to the tail. The skewed is determined by where the tail goes, to the right side , it is positively skewed and to the left side , it is known as negatively skewed distribution.
Given that:
In a frequency of distribution of 290 scores,
the mean = 99
the median = 86
One would expect this distribution to be; positively skewed to the right since the mean value is greater than the median value.
At the end of the day of teaching the skill of cutting and sewing to make capes, Ms. Ironperson and Mr. Thoro decided to go to the Shawarma Mediterranean Grill. Ms. Ironperson ordered 3 chicken shawarma wraps and 2 orders of spiced potatoes for a total bill of $42.95. Mr. Thoro ordered 5 chicken shawarma wraps and 4 orders of spiced potatoes for a total bill of $74.91. What is the cost of a chicken shawarma wrap? What is the cost of one order of spiced potatoes? If x denotes the cost of a chicken shawarma wrap and y denotes the cost of an order of spiced potatoes, what are the equations needed to solve this problem?
Answer:
a) What is the cost of a chicken shawarma wrap?
$10.99
b) What is the cost of one order of spiced potatoes?
$4.99
c) If x denotes the cost of a chicken shawarma wrap and y denotes the cost of an order of spiced potatoes, what are the equations needed to solve this problem?
3x + 2y = $42.95 .............Equation 1
5x + 4y = $74.91 ................Equation 2
Step-by-step explanation:
Let x denotes the cost of a chicken shawarma wrap and y denotes the cost of an order of spiced potatoes,
Cost of a chicken sharwarma wrap = x
Cost of an order of spiced potatoes = y
Ms. Ironperson ordered 3 chicken shawarma wraps and 2 orders of spiced potatoes for a total bill of $42.95.
3x + 2y = $42.95 .............Equation 1
Mr. Thoro ordered 5 chicken shawarma wraps and 4 orders of spiced potatoes for a total bill of $74.91.
5x + 4y = $74.91 ................Equation 2
Hence, the Equations needed to solve the question is:
3x + 2y = $42.95 .............Equation 1
5x + 4y = $74.91 ................Equation 2
We use Elimination method to solve for this.
Multiply Equation 1 by coefficient of x in Equation 2
Equation 2 by coefficient of x in Equation 1
3x + 2y = $42.95 .............Equation 1 × 5
5x + 4y = $74.91 ................Equation 2 × 3
15x + 10y = 214.75..............Equation 3
15x + 12y = 224.73..............Equation 4
Subtract Equation 3 from Equation 4
2y = 9.98
y = 9.98/2
y = 4.99
Therefore, y = Cost of an order of spiced potatoes = $4.99
Subtitute 4.99 for y in Equation 1
3x + 2y = $42.95 .............Equation 1
3x +2(4.99) = 42.95
3x + 9.98 = 42.95
3x = 42.95 - 9.98
3x = 32.97
x = 32.97/3
x = 10.99
x = Cost of a chicken sharwarma wrap = $10.99
Therefore,
The cost of a chicken sharwarma wrap = $10.99
The cost of an order of spiced potatoes = $4.99
Find the next term of the sequence.
16, 9, 2, -5,
Answer: The next term is -12.
Step-by-step explanation:
16,9,2,-5
Looking at these numbers to go from 16 to 9 you will add -7 or subtract 7 . The same way you subtract 7 from 9 to get 2 and subtract 7 from 2 to get -5.
So to determine the next term subtract 7 from -7 or add -7.
-5 - 7 = -12
0r -5 + -7 = -12
[tex] 👋 [/tex] Hello ! ☺️
Step-by-step explanation:
•Find the next term of the sequence.
Let us find the interval between two successive terms:
16 - 9= 7
-7 is therefore the common différence of this sequence. (d)
Find the next term :
-5 + (-7)= -12
[tex]\boxed{\color{gold}{N = -12}} [/tex]
[tex]<marquee direction="left" scrollamount="2" height="100" width="150">💘Mynea04</marquee>[/tex]
An Uber driver provides service in city A and city B only dropping off passengers and immediately picking up a new one at the same spot. He finds the following Markov dependence. For each trip, if the driver is in city A, the probability that he has to drive passengers to city B is 0.25. If he is in city B, the probability that he has to drive passengers to city A is 0.45. Required:a. What is the 1-step transition matrix? b. Suppose he is in city B, what is the probability he will be in city A after two trips? c. After many trips between the two cities, what is the probability he will be in city B?
Answer:
a. 1-step transition matrix is be expressed as:
[tex]P= \left[\begin{array}{cc}0.75&0.25\\0.45&0.55\\\end{array}\right][/tex]
b. The probability that he will be in City A after two trips given that he is in City B = 0.585
c. After many trips, the probability that he will be in city B = 0.3571
Step-by-step explanation:
Given that:
For each trip, if the driver is in city A, the probability that he has to drive passengers to city B is 0.25
If he is in city B, the probability that he has to drive passengers to city A is 0.45.
The objectives are to calculate the following :
a. What is the 1-step transition matrix?
To determine the 1 -step transition matrix
Let the State ∝ and State β denotes the Uber Driver providing service in City A and City B respectively.
∴ The transition probability from state ∝ to state β is 0.25.
The transition probability from state ∝ to state ∝ is 1- 0.25 = 0.75
The transition probability from state β to state ∝ is 0.45. The transition probability from state β to state β is 1 - 0.45 = 0.55
Hence; 1-step transition matrix is be expressed as:
[tex]P= \left[\begin{array}{cc}0.75&0.25\\0.45&0.55\\\end{array}\right][/tex]
b. Suppose he is in city B, what is the probability he will be in city A after two trips?
Consider [tex]Y_n[/tex] = ∝ or β to represent the Uber driver is in City A or City B respectively.
∴ The probability that he will be in City A after two trips given that he is in City B
=[tex]P(Y_0 = 2, Y_2 = 1 , Y_3 = 1) + P(Y_0 = 2, Y_2 = 2 , Y_3 = 1)[/tex]
= 0.45 × 0.75 + 0.55 × 0.45
= 0.3375 + 0.2475
= 0.585
c. After many trips between the two cities, what is the probability he will be in city B?
Assuming that Ф = [ p q ] to represent the long run proportion of time that Uber driver is in City A or City B respectively.
Then, ФP = Ф , also p+q = 1 , q = 1 - p and p = 1 - q
∴
[tex][ p\ \ \ q ] = \left[\begin{array}{cc}0.75&0.25\\0.45&0.55\\\end{array}\right] [ p\ \ \ q ][/tex]
0.75p + 0.45q = q
-0.25p + 0.45q = 0
since p = 1- q
-0.25(1 - q) + 0.45q = 0
-0.25 + 0.25 q + 0.45q = 0
0.7q = 0.25
q = [tex]\dfrac{0.25} {0.7 }[/tex]
q = 0.3571
After many trips, the probability that he will be in city B = 0.3571
Find the missing side or angle.
Round to the nearest tenth.
Answer:
b=2.7
Step-by-step explanation:
using sine rule,,,
Step-by-step explanation:
So for this problem, we need the missing angle A. From there, we can use the law of sines to compute length of b.
So the sum of the interior angles of a triangle is 180. With that in mind, we can make an equation to fine the measure of angle A.
53 + 80 + A = 180
133 + A = 180
A = 47
Now that we have the angle of A, we can use the law of sines to fine the length of b.
b / sin(B) = a / sin(A)
b = sin(B) * a / sin(A)
b = sin(80) * 2 / sin(47)
b = 2.693
Now round that to the nearest tenth to get
b = 2.7
Cheers.
Suppose babies born in a large hospital have a mean weight of 3316 grams, and a standard deviation of 324 grams. If 83 babies are sampled at random from the hospital, what is the probability that the mean weight of the sample babies would differ from the population mean by greater than 54 grams?
Answer: 0.129
Step-by-step explanation:
Let [tex]\overline{X}[/tex] denotes a random variable that represents the mean weight of babies born.
Population mean : [tex]\mu= \text{3316 grams,}[/tex]
Standard deviation: [tex]\text{324 grams}[/tex]
Sample size = 83
Now, the probability that the mean weight of the sample babies would differ from the population mean by greater than 54 grams will be :
[tex]P(|\mu-\overline{X}|>54)=1-P(\dfrac{-54}{\dfrac{324}{\sqrt{83}}}<\dfrac{\overline{X}-\mu}{\dfrac{\sigma}{\sqrt{n}}}<\dfrac{-54}{\dfrac{324}{\sqrt{83}}})\\\\=1-[P(-1.518<Z<1.518)\ \ \ [Z=\dfrac{\overline{X}-\mu}{\dfrac{\sigma}{\sqrt{n}}}]\\\\=1-[P(Z<1.518)-P(z<-1.518)]\\\\=1-[P(Z<1.518)-(1-P(z<1.518))]\\\\=1-[2P(Z<1.518)-1]=2-2P(Z<1.518)\\\\=2-2(0.9355)\ [\text{By z-table}]\\\\=0.129[/tex]
hence, the required probability = 0.129
Find the value of the test statistic to test for a difference in the areas. Round your answer to two decimal places, if necessary.
Answer:
hello your question has some missing parts attached below is a picture of the complete question
Answer : 3.59
Step-by-step explanation:
Calculating the standard deviation, mean and standard error of the hourly wages
Area 1 : mean = 12.75 , std = 4.9497 , std error = 1.75
Area 2 : mean = 18.25, std = 4.3671, std error = 1.54399
Area 3 : mean = 16.25, std = 2.8660, std error = 1.01330
mean = sum of terms / number of terms
std = [tex]\sqrt{}[/tex] (X − μ)2 / n
std error = std / [tex]\sqrt{n}[/tex]
The value of the test statistic to test for a difference in the areas is
3.59 ( using anova table attached below )
Determine the Perimeter of the shape #1.
Answer:
56.8
Step-by-step explanation:
7.1*8=56.8
donald is a taxi driver. for each ride in the taxi, the cost, c, is given by c = 500+130d, where c is in cents and d is the distance of the ride, in miles. what is the meaning of the value 500 in this equation? a) donald charges 500 cents per mile b) donald drives 500 customers per day c) donald charges at least 500 cents per taxi ride d) donald charges at most 500 cents per taxi ride
can u go to my page real quick and answer my question pls
A box is filled with 8 blue cards, 6 red cards, and 6 yellow cards. A card is chosen at a random from the box. What is the probability that the card is not red ? Write your answer as a fraction.
Answer:
14/20 or .7 or 70%
Step-by-step explanation:
Total Number of cards: 20
Number of Red cards: 6
The leftover cards: 20 -6 = 14
The probability of not getting a red = 14/20
14/20 as a decimal = 14/20 = 70/100 = .7
14/20 as a percent = 14/20 = 70/100 = 70%
