The expected standard deviation of stock A's returns, based on the information presented in the table, is approximately 23.57%.
To calculate the expected standard deviation of stock A's returns, we first need to calculate the variance. The variance is the average of the squared deviations from the expected return, weighted by the probabilities of each outcome.
Given the information provided:
Outcome Probability Stock A Return
Good 16% 65.00%
Medium 51% 17.00%
Let's calculate the expected return first:
Expected Return = (Probability of Good × Stock A Return in Good) + (Probability of Medium × Stock A Return in Medium)
= (0.16 × 65.00%) + (0.51 × 17.00%)
= 10.40% + 8.67%
= 19.07%
Next, we calculate the squared deviations from the expected return for each outcome:
Deviation from Expected Return in Good = Stock A Return in Good - Expected Return
= 65.00% - 19.07%
= 45.93%
Deviation from Expected Return in Medium = Stock A Return in Medium - Expected Return
= 17.00% - 19.07%
= -2.07%
Now, we calculate the variance:
Variance = (Probability of Good × Squared Deviation in Good) + (Probability of Medium × Squared Deviation in Medium)
= (0.16 × (45.93%^2)) + (0.51 × (-2.07%^2))
= (0.16 × 0.2110) + (0.51 × 0.0428)
= 0.0338 + 0.0218
= 0.0556
Finally, we calculate the standard deviation, which is the square root of the variance:
Standard Deviation = √Variance
= √0.0556
= 0.2357 or approximately 23.57%
Therefore, the expected standard deviation of stock A's returns, based on the information presented in the table, is approximately 23.57%.
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the radius of a circle is 18.4 inches. the circle's circumference is about ___ inches.
use 3.14 for pi
Answer:
115.552 or 116 inches.
Step-by-step explanation:
Use the circumference of a circle formula which is C= 2piR. Where C is circumference and R is radius. So you get C=2(3.14×18.4) which gives you 115.552.
can someone plz help me wit dis plz
Answer:
b = 6.1 ft
Step-by-step explanation:
The area (A) of a triangle is calculated as
A = [tex]\frac{1}{2}[/tex] bh ( b is the base and h the perpendicular height )
Here A = 10.98 and h = 3.6 , then
[tex]\frac{1}{2}[/tex] × b × 3.6 = 10.98
1.8b = 10.98 ( divide both sides by 1.8 )
b = 6.1
0
Tickets to a movie cost $9.00 for adults and $5.50 for students. There were 150 tickets purchased for a total of $1,105.00. The following system of
equations models the situation, where a is the number of adult tickets purchased and s is the number of student tickets purchased. Write the
terms with the variables in alphabetical order.
9a + 5.5s = 1.105
a +5 = 150
Rewrite the second equation in the system so that the variable for the number of adult tickets purchased can be eliminated by subtraction.
Answer:
150a
Step-by-step explanation:
The matrix A has eigenvalues X₁ = 3 and X₂ = 4 with associated eigenvectors 2 V₁ = and v2 [A] Use this information to find the solution to the initial value - [³] Y' = AY where Y (0) = [ (0)] - [8] - [ 2₂ ] 1 problem = Give your answer as x(t) and y(t). y
The solution to the initial value problem is:
x(t) = [tex](1/4) * e^{(3t)} - (1/4) * e^{(4t)}[/tex] and y(t) = [tex]e^{(3t)} + (1/6) * e^{(4t)}[/tex]
To find the solution to the initial value problem Y' = AY, where A is the matrix with eigenvalues and eigenvectors given, we can use the eigenvalue-eigenvector method.
Let's denote the eigenvectors as v₁ and v₂:
v₁ = [2]
[8]
v₂ = [-3]
[2]
The general solution to the system of linear differential equations can be written as:
Y(t) = [tex]c_1 * e^{(X_1t)} * v_1 + c_2 * e^{(X_2t)} * v_2[/tex]
where c₁ and c₂ are constants.
Substituting the given eigenvalues and eigenvectors:
Y(t) = c₁ * [tex]e^{(3t)[/tex] * [2] + c₂ * [tex]e^(4t)[/tex] * [-3]
[8] [2]
Simplifying further:
Y(t) = [2c₁ * [tex]e^{(3t)[/tex] - 3c₂ * [tex]e^{(4t)[/tex]]
[8c₁ * [tex]e^{(3t)[/tex] + 2c₂ * [tex]e^{(4t)[/tex]]
To find the specific solution that satisfies the initial condition Y(0) = [0] and [8], we can substitute t = 0 into the general solution:
Y(0) = [2c₁ - 3c₂]
[8c₁ + 2c₂]
Equating this to the initial condition:
[2c₁ - 3c₂] = [0]
[8c₁ + 2c₂] [2]
Solving this system of equations will give us the values of c₁ and c₂:
2c₁ - 3c₂ = 0 ----(1)
8c₁ + 2c₂ = 2 ----(2)
Multiplying equation (1) by 4 and adding it to equation (2), we get:
16c₁ = 2
Solving for c₁, we find:
c₁ = 1/8
Substituting c₁ back into equation (1), we can solve for c₂:
2(1/8) - 3c₂ = 0
1/4 - 3c₂ = 0
3c₂ = 1/4
c₂ = 1/12
Therefore, the specific solution to the initial value problem is:
x(t) = [tex](1/8) * e^{(3t)} * 2 + (1/12) * e^{(4t) }* (-3)[/tex]
y(t) = [tex](1/8) * e^{(3t)} * 8 + (1/12) * e^{(4t)} * 2[/tex]
Simplifying further:
x(t) = [tex](1/4) * e^{(3t)} - (1/4) * e^{(4t)}[/tex]
y(t) = [tex]e^{(3t)} + (1/6) * e^{(4t)}[/tex]
Therefore, the solution to the initial value problem is x(t) = [tex](1/4) * e^{(3t)} - (1/4) * e^{(4t)}[/tex] and y(t) = [tex]e^{(3t)} + (1/6) * e^{(4t)}[/tex].
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A size 8 kid's shoe measures 9 2/3 inches. If 5 size 8 shoes are lined end to end, then how many inches will they cover?
Answer:
its 77 1/3
just do the math with a calculator
Answer: 48 1/3
Step-by-step explanation:
I really need help fast and ill do anything just help me plz
PLS HELP ILL MARK AS MY BRAINLESS
Answer:
They a similar because they both had zero as their final answer. Andre decided to do 3 x 200 while Jada decided to do 3 x 50. Andre work is more complicated and uses big number while Jada's work uses small numbers and are more easier to do.
Step-by-step explanation:
please help me it's worth 10+ points
Answer:
10, 12 and 11
Step-by-step explanation:
On each median , the distance from the vertex to the centroid is twice as long as the distance from the centroid to the midpoint.
TZ = 2 × ZX = 2 × 5 = 10
UY = UZ + ZY = 8 + 4 = 12
ZW = [tex]\frac{1}{3}[/tex] × VW = [tex]\frac{1}{3}[/tex] × 33 = 11
HELP ME PLEASEEEEEEE CIRCUMFERENCE AND AREA OF A CIRCLE
Answer:
Formula for circumference: 2 x pie(3.14 or 22/7) x radius(half of diameter or already given radius). Area of a circle: pie(3.14 or 22/7) x radius squared
Radius: 3, 6 is diameter and half of that is 3.
3 x 3.14 x 2 = 18.84 <------ circumference
3.14 x 3^2
3.14 x 9 = 28.26 <------ area of the circle
simplify the expression: (4 3i)(2 − 8i).
a. 32 – 26i
b. −16 26 i
c. 32 38i
d. −16 38i
The correct answer should be 32.
To simplify the expression (4 + 3i)(2 - 8i), we can use the distributive property of multiplication.
First, we multiply the real parts of the two complex numbers:
(4)(2) = 8.
Next, we multiply the imaginary parts of the two complex numbers:
(3i)(-8i) = -24i^2.
Remember that i^2 is defined as -1, so we can substitute -1 for i^2:
-24i^2 = -24(-1) = 24.
Now, we combine the real and imaginary parts:
8 + 24 = 32.
Therefore, the simplified expression is 32.
Since none of the given answer choices match the simplified expression, it appears that there may be an error in the options provided. The correct answer should be 32.
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Mia is working two summer jobs, making $11 per hour babysitting and making $20 per hour lifeguarding. In a given week, she can work a maximum of 15 total hours and must earn no less than $220. If x represents the number of hours babysitting and y represents the number of hours lifeguarding, write and solve a system of inequalities graphically and determine one possible solution.
Answer: 11x + 20y ≥ 220
x + y ≤ 15
Hope this helps
9514 1404 393
Answer:
x + y ≤ 1511x +20y ≥ 2203 hours babysitting and 11 hours lifeguardingStep-by-step explanation:
The two inequalities represent the two relations described in the problem statement.
x + y ≤ 15 . . . . . . . Mia works a maximum of 15 hours
11x + 20y ≥ 220 . . . . Mia makes at least $220
These are graphed in the attachment. The solution area is the doubly-shaded area with vertices at (9, 6), (0, 11) and (0, 15). One possible solution is shown at (3, 11), which represents ...
3 hours babysitting
11 hours lifeguarding . . . . . . . . total 14 hours for $253
Please help these are just practice problems before my test tomorrow and I need help!
Answer:
x²=20² -14²
x²=400-196
x²=204
x=√204
Which decimal is closest in value to the fraction below? 1/6
Answer:
0.1666...
Step by step explanation:
By using long division (with 6 as the divisor) the number sentence would keep on going with 40-36.
0.166666666
1.000000000
− 0
10
− 6
40
−36
40
−36
40
− 36
40
− 36
40
− 36
40
− 36
40
− 36
40
− 36
A survey asked, "How many tattoos do you currently have on your body?" Of the 1233 males surveyed, 190 responded that they had at least one tattoo. Of the 1033 females surveyed,128
responded that they had at least one tattoo. Construct a 99% confidence interval to judge whether the proportion of males that have at least one tattoo differs significantly from the proportion of females that have at least one tattoo. Interpret the interval.
Let p1 represent the proportion of males with tattoos and p2 represent the proportion of females with tattoos. Find the 99% confidence interval for p1−p2.
The lower bound ___ your response here.
The upper bound is ___ (Round to three decimal places as needed.)
Interpret the interval.
A.There is 99% confidence that the difference of the proportions is in the interval. Conclude that there is insufficient evidence of a significant difference in the proportion of males and females that have at least one tattoo.
B.There is a 99% probability that the difference of the proportions is in the interval. Conclude that there is insufficient evidence of a significant difference in the proportion of males and females that have at least one tattoo.
C.There is a 99% probability that the difference of the proportions is in the interval. Conclude that there is a significant difference in the proportion of males and females that have at least one tattoo.
D.There is 99% confidence that the difference of the proportions is in the interval. Conclude that there is a significant difference in the proportion of males and females that have at least one tattoo.
There is insufficient evidence of a significant difference in the proportion of males and females that have at least one tattoo.
Therefore, the correct answer is A.
To construct a confidence interval for the difference in proportions, we can use the following formula:
CI = (p1 - p2) ± Z ×√[(p1×(1 - p1) / n1) + (p2 × (1 - p2) / n2)]
Where:
p1 and p2 are the sample proportions for males and females, respectively.
n1 and n2 are the sample sizes for males and females, respectively.
Z is the critical value corresponding to the desired confidence level.
From the given information, we have:
p1 = 190/1233
n1 = 1233
p2 = 128/1033
n2 = 1033
Confidence level = 99% (which corresponds to a critical value of Z)
Calculating the confidence interval:
CI = (190/1233 - 128/1033) ± Z× √[(190/1233× (1 - 190/1233) / 1233) + (128/1033 ×(1 - 128/1033) / 1033)]
Now, let's find the critical value Z for a 99% confidence level. Since the sample sizes are large, we can use the standard normal distribution. The critical value for a 99% confidence level is approximately 2.576.
CI = (0.154 - 0.124) ± 2.576× √[(0.154× (1 - 0.154) / 1233) + (0.124 × (1 - 0.124) / 1033)]
CI = 0.030 ± 2.576×√[0.000118 + 0.000124]
CI = 0.030 ± 2.576×√(0.000242)
CI = 0.030 ± 2.576×0.015556
CI = 0.030 ± 0.040085
CI ≈ (-0.010, 0.070)
The lower bound of the 99% confidence interval is approximately -0.010, and the upper bound is approximately 0.070.
Interpreting the interval, we can say:
A. There is 99% confidence that the difference of the proportions is in the interval. Conclude that there is insufficient evidence of a significant difference in the proportion of males and females that have at least one tattoo.
Therefore, the correct answer is A.
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plz help me please please
Answer:
5%
Step-by-step explanation:
Answer:
5% increase
Step-by-step explanation:
30/600 equals .05 or 5%
What is the value of x?
Answer:
106
Step-by-step explanation:
reflection
Are these proportional?
6/9 and 2/3
Answer:
yes.
Step-by-step explanation:
Ratios are proportional if they represent the same relationship. One way to see if two ratios are proportional is to write them as fractions and then reduce them. If the reduced fractions are the same, your ratios are proportional.
6/9 divided by 3/3= 2/3
proportional
Please help me someone.!!!!!!!!!!!!!!!!!!!!
Answer:
[tex]y=-|x|+2[/tex]
Step-by-step explanation:
The y-intercept is 2 and the line of symmetry is the y-axis.
Please help!!! I’ll mark you as brainliest!!!!!!
0.138613961 as a percent rounded to the nearest tenth
Answer:
13.9% Approximately
A right prism has a volume of 65 cubic inches. The prism is enlarged so its height is increased by a factor of 20, but the other dimensions do not change. What is the new volume? A. 1000in.3 B. 1300in.3 C. 1200in.3 D. 1100in.3
Answer:
The answer is B, have a wonderful day!
Step-by-step explanation:
Now, the Group of Good would like to decide how they should infiltrate the gallery. The group wants to vote on different plans to sneak into the gallery; the plans are labelled a - e. While the group puts all of the plans together so everyone can see them, a tragedy occurs. Kenny gets a paper cut by Plan a! The cut is too deep! Saddened by their colleague’s sudden paper death, they decide that the leader should have more say in which plan is picked (in hopes to avoid more unnecessary death). Suppose the leader’s vote (from the last question) counts as 5 votes. The following preference schedule is produced:
Total Votes = 2 2 1 1
Choice 1 e c a b b
Choice 2 d a b d a
Choice 3 c d e c d
Choice 4 a b d e c
Choice 5 b e c a e
(a) If plurality voting is used, what plan should the group use? Does this plan have a majority
Total Votes = 2 2 1 1
Choice 1 e c a b b
Choice 2 d a b d a
Choice 3 c d e c d
Choice 4 a b d e c
Choice 5 b e c a e
(b) If Instant Runoff Voting is used, what plan should the group use? Show how you discovered your answer.
Total Votes = 2 2 1 1
Choice 1 e c a b b
Choice 2 d a b d a
Choice 3 c d e c d
Choice 4 a b d e c
Choice 5 b e c a e
(c)If the Borda Count method is used, what plan should the group use? Show how the winner is computed
What was the best part of this project? What was the worst part?
(a) If plurality voting is used, Plan E will be chosen.
b It has the most first-place votes, with 2 each from voters 1 and 5. No other plan has more than 1 first-place vote.
c If the Borda Count method is used, Plan C will be chosen.
How to explain the informationa The best part of this project was learning about different voting methods and how they can be used to choose a winner. The worst part of the project was the difficulty of calculating the Borda Count.
b If Instant Runoff Voting is used, Plan C will be chosen. In the first round of counting, Plan E is eliminated, as it has the fewest first-place votes. In the second round, Plan C is eliminated, as it has the fewest second-place votes. In the third round, Plan B is eliminated, as it has the fewest third-place votes. In the fourth round, Plan D is eliminated, as it has the fewest fourth-place votes. This leaves Plan A as the winner, as it has the most votes remaining.
c If the Borda Count method is used, Plan C will be chosen. Each voter's ballot is assigned a number of points equal to the number of candidates ranked lower than that candidate. For example, voter 1's ballot gives Plan E 5 points, Plan C 4 points, Plan A 3 points, Plan B 2 points, and Plan D 1 point. The total number of points for each candidate is then calculated. Plan C has the most points, with 16, so it is the winner.
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Which of the following is a research question that could be addressed using a one-way analysis of variance?
A. Does mean blood pressure differ for three different age groups?
B. Does the variance of blood pressure differ for three different age groups?
C. Are the proportions of people who oppose wearing masks different for different age groups?
D. Is there a relationship between political party preference and age?
E. Is Final Grade for a subject (H1, H2A, H2B, H3, P, N) affected by student's preferred seating location during lectures (Lecture theatre, Desk, Couch, Bed, Other)?
A. Does mean blood pressure differ for three different age groups?
This is a research question that could be addressed using a one-way analysis of variance.
A one-way analysis of variance (ANOVA) is a statistical test used to determine whether there are any significant differences between the means of three or more groups. In the given research question, we are interested in examining whether the mean blood pressure differs across three different age groups.
To address this question using a one-way ANOVA, we would collect blood pressure measurements from individuals belonging to three different age groups. We would then calculate the mean blood pressure for each group and compare these means statistically. The one-way ANOVA test would allow us to determine if there is enough evidence to suggest that the mean blood pressure differs significantly between the age groups.
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Factor the expression over the complex numbers. x2+20 Enter your answer in the box.
Answer:
2(x plus 20)
Step-by-step explanation:
this is the highest common factor
please helpppp
also just click the image for it to be bigger
Suppose there is a family with four children. Assume that it is equally probable for a boy or a girl to be born. a. What is the probability of all girls? b. What is the probability of all girls given there is at west one girl? c. What is the probability of at least one boy and one girl?
a. The probability of all girls in a family with four children is 1/16 or 0.0625.
b. The probability of all girls given there is at least one girl is 1/15 or 0.0667.
c. The probability of having at least one boy and one girl in a family with four children is 15/16 or 0.9375.
a. To calculate the probability of all girls, we need to consider the possible outcomes of each child being a girl. Since each child has an independent probability of being a girl or a boy, the probability of all girls is (1/2) * (1/2) * (1/2) * (1/2) = 1/16 or 0.0625.
b. Given that there is at least one girl, we have three remaining children. The probability of all girls among the three remaining children is (1/2) * (1/2) * (1/2) = 1/8. Therefore, the probability of all girls given there is at least one girl is 1/8 divided by the probability of having at least one girl, which is 1 - (1/2)⁴ = 15/16, resulting in a probability of 1/15 or approximately 0.0667.
c. The probability of having at least one boy and one girl can be calculated by subtracting the probability of having all boys from the total probability space. The probability of having all boys is (1/2)⁴ = 1/16. Therefore, the probability of having at least one boy and one girl is 1 - 1/16 = 15/16 or approximately 0.9375. This probability accounts for all possible combinations of boys and girls in a family with four children, excluding the scenario of having all boys.
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Use iteration to guess an explicit formula for the following sequence - dx = 2dx-1 + 3k2 , for all integers k> 1 and do = 3 You must show your work.
By using iteration, we can guess the explicit formula for the given sequence. It is found that the sequence follows a quadratic pattern, and the explicit formula is dx = 3([tex]2^{k-1}[/tex]) + 3[tex]k^2[/tex] - 6k + 3.
Let's start by analyzing the given sequence: dx = 2dx-1 + 3[tex]k^2[/tex]. We are given that d1 = 3. We can use this initial value to find d2, d3, and so on.
Substituting k = 2 into the given equation, we get d2 = 2d1 + 3([tex]2^2[/tex]) = 2(3) + 3(4) = 6 + 12 = 18.
Similarly, substituting k = 3, we get d3 = 2d2 + 3[tex](3^2)[/tex] = 2(18) + 3(9) = 36 + 27 = 63.
Based on these calculations, we observe that each term in the sequence is related to the previous term by multiplying it by 2 and adding 3[tex]k^2[/tex]. Moreover, we notice a quadratic pattern in the sequence.
To find the explicit formula, we can express dx in terms of k:
dx = 2dx-1 + 3[tex]k^2[/tex]
= 2(2dx-2 + 3[tex](k-1)^2[/tex]) + 3[tex]k^2[/tex]
= 4dx-2 + 6[tex](k-1)^2[/tex][tex](k-1)^2[/tex] + 3[tex]k^2[/tex].
We can continue this iteration process, expanding dx-2 in terms of dx-3, and so on. By continuing this process and simplifying the equation, we find that the explicit formula for the sequence is dx = 3([tex]2^{k-1}[/tex]) + 3[tex]k^2[/tex] - 6k + 3.
In conclusion, by using iteration, we have determined that the explicit formula for the given sequence dx = 2dx-1 + 3[tex]k^2[/tex], with d1 = 3, is dx = 3([tex]2^{k-1}[/tex]) + 3[tex]k^2[/tex] - 6k + 3.
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write rational number in number line -7 upon 2
Answer:
el numero 1
Step-by-step explanation:
NO LINKSS !! I WILL REPORT !! HELPP ME PLSS I I WASTED MOST OF MY POINTSS AND NO ONE ENDS UP HELPING ME PLSSS HELP ME Write the slope-intercept inequality for the graph below. If necessary, use <=
fors or > = for >
Answer: Y less than -3x – 3
Step-by-step explanation:
A steam power plant operates on the ideal reheat-pipe steam Rankine cycle and generates 90 MW of net power. Steam enters the high pressure turbine at a pressure of 10 MPa and a temperature of 520° and exits at a pressure of 1 MPa. Some steam leaving the turbine at this pressure is used to heat the boiler feedwater in an open feedwater heater. After the remaining steam is heated to 480°, it is expanded in the low pressure turbine to a condenser pressure of 14 kPa. Calculate the mass flow rate of the steam passing through the boiler and the thermal efficiency of the cycle by showing the cycle in a T-s diagram with saturated liquid and saturated steam curves.
The mass flow rate is 0.56 kg/s
How to determine the mass flow rateThe formula for calculating the mass flow rate is expressed as;
m = W / (hf - hg)
Such that the parameters are expressed as;
m is the mass flow rate (kg/s)W is the net power output (W)hf is the enthalpy of the feedwater (kJ/kg)hg is the enthalpy of the steam at the turbine exit (kJ/kg)Substitute the values, we get;
m = 90 MW / (2418 - 2257)
Subtract the values, we have;
m = 90/161
Divide the values, we get;
m= 0.56 kg/s
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Last year the records of a convenience store chain showed the mean amount spent by a customer was $52. A sample of 36 transactions made this month revealed the mean amount spent was $50 with a standard deviation of $11. At the 0.10 significance level, test the claim that the mean amount spent by a customer has significantly decreased since last year.
There insufficient evidence to support the claim that the mean amount spent by a customer has significantly decreased since last year.
Step 1: State the hypotheses:
- Null hypothesis (H0): The mean amount spent by a customer is equal to or greater than last year's mean ($52).
- Alternative hypothesis (H1): The mean amount spent by a customer is significantly less than last year's mean ($52).
Step 2: Set the significance level:
The significance level (α) is given as 0.10. This represents a 10% chance of rejecting the null hypothesis when it is true.
Step 3: Formulate the decision rule:
Since the alternative hypothesis is stating a decrease in the mean amount spent, we will conduct a one-tailed t-test and reject the null hypothesis if the test statistic falls in the critical region corresponding to the left tail of the t-distribution.
Step 4: Calculate the test statistic:
We need to calculate the t-statistic using the formula:
t = (sample mean - population mean) / (sample standard deviation / √(sample size))
Given data:
Population mean (μ) = $52
Sample mean (X) = $50
Sample standard deviation (s) = $11
Sample size (n) = 36
Plugging in the values:
t = ($50 - $52) / ($11 / √(36))
t = -2 / ($11 / 6)
t ≈ -1.0909
Step 5: Determine the critical value and make a decision:
Since the significance level is 0.10 and the test is one-tailed to the left, we need to find the critical t-value at a 0.10 significance level with degrees of freedom equal to (n - 1) = (36 - 1) = 35.
so, the critical t-value is -1.3104.
Since the calculated t-statistic (-1.0909) does not fall in the critical region (t < -1.3104), we do not have enough evidence to reject the null hypothesis.
Step 6: State the conclusion:
Based on the data and the hypothesis test, at the 0.10 significance level, there is insufficient evidence to support the claim that the mean amount spent by a customer has significantly decreased since last year.
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