Answer:
Step-by-step explanation:
Mean = (11.4 + 13.9 + 11.2 + 14.5 + 15.2 + 8.1 + 12.4 + 8.6 + 10.5 + 17.1 + 9.8 + 15.9)/12 = 12.4
Standard deviation = √(summation(x - mean)²/n
n = 12
Summation(x - mean)² = (11.4 - 12.4)^2 + (13.9 - 12.4)^2 + (11.2 - 12.4)^2+ (14.5 - 12.4)^2 + (15.2 - 12.4)^2 + (8.1 - 12.4)^2 + (12.4 - 12.4)^2 + (8.6 - 12.4)^2 + (10.5 - 12.4)^2 + (17.1 - 12.4)^2 + (9.8 - 12.4)^2 + (15.1 - 12.4)^2 = 89.62
Standard deviation = √(89.62/13) = 2.7
We would set up the hypothesis test. This is a test of a single population mean since we are dealing with mean
a) For the null hypothesis,
µ ≤ 15
For the alternative hypothesis,
µ > 15
This is a right tailed test
b) Since the number of samples is small and no population standard deviation is given, the distribution is a student's t.
Since n = 12,
Degrees of freedom, df = n - 1 = 12 - 1 = 11
t = (x - µ)/(s/√n)
Where
x = sample mean = 12.4
µ = population mean = 15
s = samples standard deviation = 2.7
t = (12.4 - 15)/(2.7/√12) = - 3.34
We would determine the p value using the t test calculator. It becomes
p = 0.0034
c) Assuming level of significance = 0.05.
Since alpha, 0.05 > than the p value, 0.0034, then we would reject the null hypothesis. Therefore, At a 5% level of significance, we can conclude that the water from this source does meets the EPA standard. They are higher than 15ppb
Using the t-distribution, we have that:
a)
The null hypothesis is: [tex]H_0: \mu \geq 15[/tex]
The alternative hypothesis is: [tex]H_1: \mu < 15[/tex]
b) The p-value is of 0.0051.
c) Since the p-value is of 0.0051, which is less than the standard significance level of 0.0051, it can be concluded that the mean is less than 15 ppb, and thus, this source meets the EPA standard.
Item a:
At the null hypothesis, it is tested if the mean is of at least 15 ppb, that is:
[tex]H_0: \mu \geq 15[/tex]
At the alternative hypothesis, it is tested if the mean is of less than 15 ppb, that is:
[tex]H_1: \mu < 15[/tex]
Item b:
We have the standard deviation for the sample, thus, the t-distribution is used. The test statistic is given by:
[tex]t = \frac{\overline{x} - \mu}{\frac{s}{\sqrt{n}}}[/tex]
The parameters are:
[tex]\overline{x}[/tex] is the sample mean. [tex]\mu[/tex] is the value tested at the null hypothesis. s is the standard deviation of the sample. n is the sample size.In this problem, we have that [tex]\mu = 15, n = 12[/tex]. Additionally, using a calculator, the other parameters are: [tex]\overline{x} = 12.38, s = 2.93[/tex]
Hence, the value of the test statistic is:
[tex]t = \frac{\overline{x} - \mu}{\frac{s}{\sqrt{n}}}[/tex]
[tex]t = \frac{12.38 - 15}{\frac{2.93}{\sqrt{12}}}[/tex]
[tex]t = -3.1[/tex]
The p-value is found using a left-tailed test, as we are testing if the mean is less than a value, with t = -3.1 and 12 - 1 = 11 df.
Using a calculator, this p-value is of 0.0051.Item c:
Since the p-value is of 0.0051, which is less than the standard significance level of 0.0051, it can be concluded that the mean is less than 15 ppb, and thus, this source meets the EPA standard.
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What is the difference of the polynomials? (–2x3y2 + 4x2y3 – 3xy4) – (6x4y – 5x2y3 – y5)
Answer:
-6x⁴y - 2x³y² + 9x²y³ - 3xy⁴ + y⁵
Step-by-step explanation:
(–2x³y² + 4x²y³ – 3xy⁴) – (6x⁴y – 5x²y³ – y⁵)=
–2x³y² + 4x²y³ – 3xy⁴ – 6x⁴y + 5x²y³ + y⁵=
-6x⁴y - 2x³y² + 9x²y³ - 3xy⁴ + y⁵
Five thousand tickets are sold at $1 each for a charity raffle. Tickets are to be drawn at random and monetary prizes awarded as follows: 1 prize of $ 500 500, 3 prizes of $ 200 200, 5 prizes of $ 10 10, and 20 prizes of $5. What is the expected value of this raffle if you buy 1 ticket?
Answer:
-$0.75
Step-by-step explanation:
For calculation of expected value first we need to find out the probability distribution for this raffle which is shown below:-
Amount Probability
500 - 1 = $499 1 ÷ 5,000
200 - 1 = $199 3 ÷ 5,000
10 - 1 = $9 5 ÷ 5,000
5 - 1 = $4 20 ÷ 5,000
-$1 5,000 - 29 ÷ 5,000 = 4,971 ÷ 5,000
Now, the expected value of raffle will be
[tex]= \$499 \times (\frac{1}{5,000}) + \$199 \times (\frac{3}{5,000}) + \$9 \times (\frac{5}{5,000}) + \$4 \times (\frac{20}{5,000}) - \$1 \times (\frac{4,971}{5,000})[/tex]
= 0.0998 + 0.1194 + 0.009 + 0.016 - 0.9942
= -$0.75
The expected value of this raffle per ticket is $ 0.25.
Given that five thousand tickets are sold at $ 1 each for a charity raffle, and tickets are to be drawn at random and monetary prizes awarded as follows: 1 prize of $ 500, 3 prizes of $ 200, 5 prizes of $ 10, and 20 prizes of $ 5, to determine what is the expected value of this raffle if you buy 1 ticket, the following calculation must be performed:
(500 + 3 x 200 + 5 x 10 + 20 x 5) / 5000 = X (500 + 600 + 50 + 100) / 5000 = X 1250/5000 = X 0.25 = X
Therefore, the expected value of this raffle per ticket is $ 0.25.
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what is the least common denominator of 4 7/9 and 2 2/3
Answer:
9
Equivalent Fractions with the LCD
4 7/9 = 43/9
2 2/3 = 24/9
For the denominators (9, 3) the least common multiple (LCM) is 9.
Therefore, the least common denominator (LCD) is 9.
4 7/9 = 43/9 × 1/1 = 43/9
2 2/3 = 8/3 × 3/3 = 24/9
Hope this helps :)
The least common denominator of 4 7/9 and 2 2/3 is 9.
Given data:
To find the least common denominator (LCD) of 4 7/9 and 2 2/3, we need to first convert both fractions to their equivalent forms with a common denominator.
The given fractions are:
4 7/9 = 4 + 7/9
2 2/3 = 2 + 2/3
To find a common denominator, we need to find the least common multiple (LCM) of the denominators 9 and 3, which is 9.
Now, let's convert the fractions to their equivalent forms with a denominator of 9:
4 7/9 = (4 * 9)/9 + (7/9) = 36/9 + 7/9 = 43/9
2 2/3 = (2 * 9)/9 + (2/3) = 18/9 + 2/3 = 20/9
The fractions 4 7/9 and 2 2/3 are now expressed with a common denominator of 9.
Hence, the least common denominator (LCD) of 4 7/9 and 2 2/3 is 9.
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Please answer this correctly I have to finish this today as this is my deadline
Answer:
r = 1.499619733762 m There is no such thing a quarter radius!
C = 9.4223886775301 m
A = 7.065 m^2
Step-by-step explanation:
Calculate r and C | Given A
Given the area of a circle calculate the radius and circumference
r = √(A / π)
C = 2πr
Agenda:
r = radius
C = circumference
A = area
π = pi = 3.1415926535898
√ = square root
In order to understand reasons why consumers visit their store, a local business conducts a survey by asking the next 100 people who visit their store to fill out a short survey. The business finds that 40 of the 100 people state that the main reason they visited the store was because the store is running a sale on coats that week. A confidence interval is constructed for the population proportion of consumers who would visit the store because of the coat sale. Which confidence interval would be the narrowest?
a. 90%
b. 99%
c. 95%
d. 85%
Answer:
d. 85%
Step-by-step explanation:
In a sample with a number n of people surveyed with a probability of a success of [tex]\pi[/tex], and a confidence level of [tex]1-\alpha[/tex], we have the following confidence interval of proportions.
[tex]\pi \pm z\sqrt{\frac{\pi(1-\pi)}{n}}[/tex]
In which
z is the zscore that has a pvalue of [tex]1 - \frac{\alpha}{2}[/tex].
The margin of error is:
[tex]M = z\sqrt{\frac{\pi(1-\pi)}{n}}[/tex]
The higher the confidence level, the higher the value of z, which means that the margin of error will be higher and the interval will be wider,
Which confidence interval would be the narrowest?
The one with the lowest confidence level. So the answer is d.
Given that (- 2, 7) is on the graph of f(x) , find the corresponding point for the function f(x + 4).
Answer:
[tex]\boxed{\ the \ corresponding\ point\ is \ (-6,7)\ }[/tex]
Step-by-step explanation:
We know that f(-2)=7
x+4 = -2 <=> x = -6
so f(-6+4) = f(-2)=7
then the corresponding point is (-6,7)
In a group, 10 freshmen have mean GPA of 3.5; 20 sophomores have a mean GPA of 2.9; 25 juniors have a mean GPA of 3.2; and 15 seniors have a mean GPA of 3.4. What is the mean of the entire group
Answer:
[tex] T_1 = 10*3.5 = 35[/tex]
[tex] T_2 = 20*2.9 = 58[/tex]
[tex] T_3 = 25*3.2 = 80[/tex]
[tex] T_4 = 15*3.4 = 51[/tex]
[tex] \bar X= \frac{T_1 +T_2 +T_3 +T_4}{10+20+25+15}= \frac{35+58+80+51}{10+20+25+15} = 3.2[/tex]
Step-by-step explanation:
For this case we have the following info given:
[tex] n_1= 10 , \bar X_1 = 3.5[/tex] for freshmen
[tex] n_2= 20 , \bar X_2 = 2.9[/tex] for sophomores
[tex] n_3= 25 , \bar X_3 = 3.2[/tex] for juniors
[tex] n_4= 15 , \bar X_4 = 3.4[/tex] for seniors
For this case we can use the formula for the sample mean in order to find the total of each group:
[tex] \bar X =\frac{\sum_{i=1}^n X_i}{n}[/tex]
[tex]T= \sum_{i=1}^n X_i = n *\bar X[/tex]
And replacing we got:
[tex] T_1 = 10*3.5 = 35[/tex]
[tex] T_2 = 20*2.9 = 58[/tex]
[tex] T_3 = 25*3.2 = 80[/tex]
[tex] T_4 = 15*3.4 = 51[/tex]
And the grand mean would be given by:
[tex] \bar X= \frac{T_1 +T_2 +T_3 +T_4}{10+20+25+15}= \frac{35+58+80+51}{10+20+25+15} = 3.2[/tex]
What is the volume of the rectangular prism?
Answer:
10ft[tex]{3}[/tex]
Step-by-step explanation:
One face has 15 blocks of 1/3 ft. You can clearly see 2 sets of blocks.
15 x 2 = 30
30 ÷ 3 or 30 x 1/3
= 10 ft cubed
ASAP! GIVING BRAINLIEST! Please read the question THEN answer CORRECTLY! NO guessing. I say no guessing because people usually guess on my questions.
Answer: f(x)=2-x^2
Step-by-step explanation:
The quadratic equation is
y=ax^2+bx+c
and c is equal to the y-intercept.
in the twi graphs shown both have the same shape but different y-intervepts.
c(the y-intercept) in the first graph is 5 and in the second graph(F) is 2.
On the graphing calculator it says that f(x)=2-x^2 is the correct answer therefore it is correct.
A sinusoid is any function whose values repeat in a periodic manner.
A. True
B. False
SUBMIT
Answer: short answer
Just checked it’s False
Hope this helps :))
Step-by-step explanation:
Answer:
B. False
Step-by-step explanation:
A P E X
What’s the correct answer for this question?
Answer:
D
Step-by-step explanation:
The volume of pyramid = 1/3 wlh
Where w = width, l = length and h = height
While,
The volume of rectangular prism = wlh
So,
The volume of pyramid = 1/3(the volume of prism)
Evaluate x - 2y when x = 5 and y = 5.
Determine whether the ordered pair satisfies the equation.
x - 2y = -5; (5,5)
Yes, the ordered pair satisfies the equation.
No, the ordered pair does not satisfy the equation.
Answer:
For the first question we just plug in the values so we get 5 - 2 * 5 = -5.
Again, for the second one we'll plug in the values and see if it's a true statement. 5 - 2 * 5 = -5 and -5 = -5 so the answer is yes.
Help asap giving branlist!!!
Answer:
D.
Step-by-step explanation:
So you know you have to have $62 as the base fee.
If you exceed 2 gigabytes, you subtract that by 2 because you want to find how many gigabytes you're going over. You then multiply it by 30 to find the cost.
You get C = 62 + 30(g - 2)
Answer:
anwser is d because it is write.
Step-by-step explanation:
Pamela is a college student. She pays tuition every semester and rent every month, and she uses cash daily for food. The expression 2x+12y+365z represents her yearly expenses. Which variable represents her rent?
Answer:
Variable y represent the rent of Pamela
Step-by-step explanation:
Given
Pamela pays tuition every semester and rent every month, and she uses cash daily for food.
lets understand what constitute semester , month and day in a year.
A semester consist of 6 months.
As a year has 12 months , a year will have 2 semester.
If one pays x for one semester then in a year one has to pay 2x .
As a year has two semester
Similarly
A year has 12 months .
If one pays y for one month then in a year one has to pay 12y .
As a A year has 12 months .
A year has 365 days
If one pays z for each month then in a year one has to pay 365z .
As a A year has 365 days.
__________________________________________
Based on above discussion , we can now safely assume that the we have to look at the coefficient of expression 2x+12y+365z to find the which variable represent which type of bill.
As we have to find variable for rent and rent is paid monthly.
so for a year total bill will have 12 months and hence going by expression variable y represent the rent of Pamela.
Ralph is 3 times as old as Sara. In 4 years, Ralph will be only tice as old as Sara will be then.
If x represents Sara's age now, which of the following expressions represents Ralph's age in four years?
A. 3x
B. 2x+4
C. 3x+4
Answer:
In 6 years, Ralph will be only twice as old as Sara
Step-by-step explanation:
Answer:
The answer is C, 3x+4
Step-by-step explanation:
The “in four years” part translates to +4. The 3x translates to 3 times his current age. Hope this helped :)
Find the length of side x in simplest radical form with a rational denominator
Answer:
[tex] x = 7 \sqrt{3} [/tex]
Step-by-step explanation:
[tex] \tan \: 30 \degree = \frac{7}{x} \\ \\ \therefore \: \frac{1}{ \sqrt{3} } = \frac{7}{x} \\ \\ x = 7 \sqrt{3} \\ [/tex]
What is the missing side length?
Answer:
8 yds
Step-by-step explanation:
The sides have to have the same length
14 yd = 6yd + ?
Subtract 6 from each side
14-6 = 8
8 yds
Jodie Meeks's Free Throws During the 2015-16 NBA season, Jodie Meeks of the Detroit Pistons had a free throw shooting percentage of 0.906 . Assume that the probability Jodie Meeks makes any given free throw is fixed at 0.906 , and that free throws are independent.If Jodie Meeks shoots 6 free throws in a game, what is the probability that he makes at least 5 of them?
Answer:
0.8973
Step-by-step explanation:
Relevant data provided in the question as per the question below:
Free throw shooting percentage = 0.906
Free throws = 6
At least = 5
Based on the above information, the probability is
Let us assume the X signifies the number of free throws
So, Then X ≈ Bin (n = 6, p = 0.906)
[tex]P = (X = x) = $\sum\limits_{x}^6 (0.906)^x (1 - 0.906)^{6-x}, x = 0,1,2,3,.., 6[/tex]
Now
The Required probability = P(X ≥ 5) = P(X = 5) + P(X = 6)
[tex]= $\sum\limits_{5}^6 (0.906)^5 (1 - 0.906)^{6-5} + $\sum\limits_{6}^6 (0.906)^6 (1 - 0.906)^{6-6}[/tex]
= 0.8973
The soup produced by a company has a salt level that is normally distributed with a mean of 5.4 grams and a standard deviation of 0.3 grams. The company takes readings of every 10th bar off the production line. The reading points are 5.8, 5.9, 4.9, 5.2, 5.0, 4.9, 6.2, 5.1, 5.7, 6.1. Is the process in control or out of control and why?
Answer:
Step-by-step explanation:
The mean of the reading points is
Mean = (5.8 + 5.9 + 4.9 + 5.2 + 5.0 + 4.9 + 6.2 + 5.1 + 5.7 + 6.1)/10 = 5.48
The process is out of control if the mean salt level of the readings is greater than 5.4
For the null hypothesis,
µ = 5.4
For the alternative hypothesis,
µ > 5.4
This is a right tailed test.
Since the population standard deviation is given, z score would be determined from the normal distribution table. The formula is
z = (x - µ)/(σ/√n)
Where
x = sample mean
µ = population mean
σ = population standard deviation
n = number of samples
From the information given,
µ = 5.4
x = 5.48
σ = 0.3
n = 10
z = (5.48 - 5.4)/(0.3/√10) = 0.84
Looking at the normal distribution table, the probability corresponding to the z score is 0.7996
The probability value to the right of the z score is 1 - 0.7996 = 0.2
Assuming a significance level of 0.05
Since alpha, 0.05 < than the p value, 0.2, then we would fail to reject the null hypothesis. Therefore, At a 5% level of significance, we can conclude that the process is not out of control. If we had rejected the null hypothesis, then our conclusion would be that the process is out of control.
uppose that the length of 20 years worth of baseball games has been investigated, and that it has been found that the average (mean) length of a game is 165 minutes and the standard deviation is 30 minutes. What is the probability that a randomly selected game will last between 120 and 210 minutes
Answer:
P(120< x < 210) = 0.8664
Step-by-step explanation:
given data
time length = 20 year
average mean time μ = 165 min
standard deviation σ = 30 min
randomly selected game between = 120 and 210 minute
solution
so here probability between 120 and 210 will be
P(120< x < 210) = [tex]P(\frac{120-165}{30}< \frac{x-\mu }{\sigma } <\frac{210-165}{30})[/tex]
P(120< x < 210) = [tex]P(\frac{-45}{30}< \frac{x-\mu }{\sigma } <\frac{45}{30})[/tex]
P(120< x < 210) = P(-1.5< Z < 1.5)
P(120< x < 210) = P(Z< 1.5) - P(Z< -1.5)
now we will use here this function in excel function
=NORMSDIST(z)
=NORMSDIST(-1.5)
P(120< x < 210) = 0.9332 - 0.0668
P(120< x < 210) = 0.8664
Please answer this correctly
Answer:
3.14
Step-by-step explanation:
We find the total circumference of a circle with radius 2 to be
2 * pi * r
= 2 * 3.14 * 2
= 12.56
We divide by 4 to get the perimeter of the quarter circle
12.56/4 = 3.14
Which number is irrational
Answer:
Can you give the question. Can you post the picture. I can help solve. I will edit this answer once you have given the question/picture.
−2.73(m+4)=−6m−4.38.
Answer:
m=2
Step-by-step explanation:
-2.73m-10.92=-6m-4.38
3.27m=6.54
m=2
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]
What is the image of (-4,12) after a dilation by a scale factor of 1/4 centered at the origin
Answer:
(-1,4)
Step-by-step explanation:
Divide each imput by 4
The required image of the given point (-4, 12) dilation by a scale factor of 1/4 and centered at the origin is (1, -3).
Given that,
To determine the image of (-4,12) after dilation by a scale factor of 1/4 centered at the origin.
The graph is a demonstration of curves that gives the relationship between the x and y-axis.
What is coordinate?Coordinate, is represented as the values on the x-axis and y-axis of the graph
Here,
For the point, we have a dilation factor of 1/4,
So dilated coordinate,
= (1/4 * - 4 , 1/4 * 12)
= (-1 , 3)
To form the image across the origin
= - (-1, 3)
= (1, -3)
Thus, the required image of the given point (-4, 12) with a scale factor of 1/4 and centered at the origin is (1, -3).
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Find the area of the triangle
Answer:
Step-by-step explanation:
The formula for the area of a triangle is base*height divided by 2. Remember this because itll be important for everything you do in math relating to geometry and calculus. Assuming you go that far
[tex]\frac{base*height}{2} =\frac{14*8}{2} =\frac{112}{2} = 56 units^2[/tex]
Answer:
A =56 units^2
Step-by-step explanation:
The area of a triangle is given by
A =1/2 bh where 14 is the base and 8 is the height
A = 1/2 (14)8
A =56 units^2
80 81 82 83 84 85 86 87 88 89 90
Anika's test scores are shown below.
Anika's Test Scores
80 81 82 83 84 85 86 87 88 89 90
Which statement compares the shape of the two dot plots?
There is a gap in both plots.
There is a gap in Anika's scores, but not in Lorenzo's scores.
The data is widely spread across both plots.
The data is more widely spread for Lorenzo's scores than for Anika's.
Mark this and return
Save and Exit
Answer:
D :)
Step-by-step explanation:
Answer:
D
Step-by-step explanation:
Braily please
The mean height of women in a country (ages 20minus29) is 64.2 inches. A random sample of 75 women in this age group is selected. What is the probability that the mean height for the sample is greater than 65 inches? Assume sigmaequals2.84. The probability that the mean height for the sample is greater than 65 inches is nothing.
Answer:
[tex] z=\frac{65-64.2}{\frac{2.84}{\sqrt{75}}} = 2.440[/tex]
And we can find the probability using the complement rule and with the normal standard table like this:
[tex] P(Z>2.440) =1-P(Z<2.440) = 1-0.993 =0.007[/tex]
The probability that the mean height for the sample is greater than 65 inches is 0.007
Step-by-step explanation:
Let X the random variable that represent the women heights of a population, and we know the following parameters
[tex]\mu=64.2[/tex] and [tex]\sigma=2.84[/tex]
We are interested on this probability
[tex]P(X>65)[/tex]
Since the sample size selected is 75>30 we can use the centrel limit theorem and the appropiate formula to use would be the z score given by:
[tex]z=\frac{x-\mu}{\frac{\sigma}{\sqrt{n}}}[/tex]
If we find the z score for 65 inches we got:
[tex] z=\frac{65-64.2}{\frac{2.84}{\sqrt{75}}} = 2.440[/tex]
And we can find the probability using the complement rule and with the normal standard table like this:
[tex] P(Z>2.440) =1-P(Z<2.440) = 1-0.993 =0.007[/tex]
The probability that the mean height for the sample is greater than 65 inches is 0.007
At the kennel, the ratio of cats to dogs is 4:5. There are 27 animals in all. How many cats are in the kennel?
Answer:
Step-by-step explanation:
4x+5x=27
9x=27
x=27/9
x=3
4x3=12
5x3=15
The total number of cats were 12.
Based on the ratio of dogs to cats in the shelter, we know that out of 27 animals, there are 12 cats.
The ratio of cats to dogs is 4:5 which means that there are 5 dogs for every 4 cats.
This means that out of 9 animals, 4 would be cats and 5 would be dogs. If there was 27 animals therefore:
= 4 / 9 x 27
= 108 / 9
= 12 cats
In conclusion, there are 12 cats.
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Skyler is out shopping and sees that striped shirts are on sale for
$19.00 each, and plaid pants are on sale for $19.50 each. He
buys 8 shirts and 6 pairs of pants. What is the total of his
purchase?
The total was $_______
Answer:
His total is $269
Step-by-step explanation:
8x19 = 152
6x19.50 = 117
152+117 = 269
