Answer:
Check the explanation
Step-by-step explanation:
Use the below R Code
Sales=c(245,138,352,322,228,275,560,366)
Advertising=c(16.5,18,22.3,17.4,19,20,32,18.6)
Commission=c(10.5,2,4,3.5,4.5,1.8,9,8.5)
data=as.data.frame(cbind(Sales,Advertising,Commission))
model1=lm(Sales~Advertising+Commission, data = data)
dat2=data.frame(Advertising=25,Commission=8)
predict(model1,dat2)
The predicted value of Sales for 25000 dollar on Advertising and 8% on Commission is 424685 dollars approximately (rounded to 0 decimal places)
The National Center for Education Statistics surveyed a random sample of 4400 college graduates about the lengths of time required to earn their bachelor’s degrees. The mean was 5.15 years and the standard deviation was 1.68 years respectively. Construct a 95% confidence interval for the mean time required to earn a bachelor’s degree by all college students. *
Answer:
95% confidence interval for the mean time required to earn a bachelor’s degree by all college students is [5.10 years , 5.20 years].
Step-by-step explanation:
We are given that the National Center for Education Statistics surveyed a random sample of 4400 college graduates about the lengths of time required to earn their bachelor’s degrees. The mean was 5.15 years and the standard deviation was 1.68 years respectively.
Firstly, the pivotal quantity for 95% confidence interval for the population mean is given by;
P.Q. = [tex]\frac{\bar X-\mu}{\frac{\sigma}{\sqrt{n} } }[/tex] ~ N(0,1)
where, [tex]\bar X[/tex] = sample mean time = 5.15 years
[tex]\sigma[/tex] = sample standard deviation = 1.68 years
n = sample of college graduates = 4400
[tex]\mu[/tex] = population mean time
Here for constructing 95% confidence interval we have used One-sample z test statistics although we are given sample standard deviation because the sample size is very large so at large sample values t distribution also follows normal.
So, 95% confidence interval for the population mean, [tex]\mu[/tex] is ;
P(-1.96 < N(0,1) < 1.96) = 0.95 {As the critical value of z at 2.5%
level of significance are -1.96 & 1.96}
P(-1.96 < [tex]\frac{\bar X-\mu}{\frac{\sigma}{\sqrt{n} } }[/tex] < 1.96) = 0.95
P( [tex]-1.96 \times {\frac{\sigma}{\sqrt{n} } }[/tex] < [tex]{\bar X-\mu}[/tex] < [tex]1.96 \times {\frac{\sigma}{\sqrt{n} } }[/tex] ) = 0.95
P( [tex]\bar X-1.96 \times {\frac{\sigma}{\sqrt{n} } }[/tex] < [tex]\mu[/tex] < [tex]\bar X+1.96 \times {\frac{\sigma}{\sqrt{n} } }[/tex] ) = 0.95
95% confidence interval for [tex]\mu[/tex] = [ [tex]\bar X-1.96 \times {\frac{\sigma}{\sqrt{n} } }[/tex] , [tex]\bar X+1.96 \times {\frac{\sigma}{\sqrt{n} } }[/tex] ]
= [ [tex]5.15-1.96 \times {\frac{1.68}{\sqrt{4400} } }[/tex] , [tex]5.15+1.96 \times {\frac{1.68}{\sqrt{4400} } }[/tex] ]
= [5.10 , 5.20]
Therefore, 95% confidence interval for the mean time required to earn a bachelor’s degree by all college students is [5.10 years , 5.20 years].
HELP PLEASE AND FAST
The city of Hamden received money for improvements of the town’s park. The park committee polled a random sample of 75 residents from the town. Of the 75 residents, 27 would like to see more trees planted in the park. From this information, what can be inferred? Most residents in the town would like to have more trees in the park. Exactly 36% of the residents in the town would like more trees in the park. About a third of the residents prefer a park improvement of more trees. Residents who use the park the most would like more trees planted.
Answer:
About a third of the residents prefer a park improvement of more trees.
Step-by-step explanation:
Less than 1/2 of the sample actually wanted more trees, so it isn't " Most residents in the town would like to have more trees in the park."
You (usually) can't get an exact answer with a sample, so it isn't ". Exactly 36% of the residents in the town would like more trees in the park."
You don't have enough data to say "Residents who use the park the most would like more trees planted."
Justin saves $8 every week. Which equation represents the amount of money Justin has, y, after x number of weeks? IF YOU PUT AN ABSURD ANSWER YOU WILL BE REPORTED, will choose brainliest.
Answer:
C
Step-by-step explanation:
Which matrix equation can be used to solve the systems of equations below?
3x - 2y = -3
6x - 5y = -9
Answer:
A. x = [ 5/3 -2/3 ] [ -3 ]
y = [ 2 -1 ] [ -9 ]
Step-by-step explanation:
got it correct on the unit test review on edge 2020
The matrix equation to solve the system of equations 3x - 2y = -3 and 6x - 5y = -9 is AX = B, where A is the coefficient matrix[tex]\(\begin{bmatrix}3 & -2 \\ 6 & -5\end{bmatrix}\)[/tex], X is the variable matrix[tex]\(\begin{bmatrix}x \\ y\end{bmatrix}\)[/tex], and B is the constant matrix[tex]\(\begin{bmatrix}-3 \\ -9\end{bmatrix}\)[/tex].
Explanation:To solve the system of linear equations presented using matrices, we can set up a matrix equation of the form AX = B, where A is the coefficient matrix, X is the variable matrix, and B is the constant matrix.
The system of equations is:
3x - 2y = -36x - 5y = -9From the system, we can identify the coefficient matrix A, the variable matrix X, and the constant matrix B as follows:
A =
[tex]\(\begin{bmatrix}3 & -2 \\ 6 & -5\end{bmatrix}\)[/tex]
X =
[tex]\(\begin{bmatrix}x \\ y\end{bmatrix}\)[/tex]
B =
[tex]\(\begin{bmatrix}-3 \\ -9\end{bmatrix}\)[/tex]
The matrix equation that can be used to solve the system is:
[tex]\(\begin{bmatrix}3 & -2 \\ 6 & -5\end{bmatrix}\) \(\begin{bmatrix}x \\ y\end{bmatrix}\) = \(\begin{bmatrix}-3 \\ -9\end{bmatrix}\)[/tex]
which is the equation of a circle with diameter AB with A(5, 4) and B(- 1, - 4)
The equation of the circle with diameter AB and endpoints A(5, 4) and B(-1, -4) is (x - 2)² + y² = 25.
We have,
To find the equation of a circle given the diameter endpoints, use the midpoint formula and the distance formula.
Given the diameter endpoints:
A(5, 4) and B(-1, -4)
Step 1:
Find the midpoint of the diameter.
The midpoint formula is given by:
Midpoint = ((x₁ + x₂) / 2, (y₁ + y₂) / 2)
Let's calculate the midpoint using the coordinates of A and B:
Midpoint = ((5 + (-1)) / 2, (4 + (-4)) / 2)
Midpoint = (4 / 2, 0 / 2)
Midpoint = (2, 0)
Step 2:
Find the radius of the circle.
The radius is the distance between the midpoint and one of the endpoints, A or B.
The distance between the midpoint and point A:
Distance = √((x₂ - x₁)² + (y₂ - y₁)²)
Distance = √((5 - 2)² + (4 - 0)²)
Distance = √(3² + 4²)
Distance = √(9 + 16)
Distance = √25
Distance = 5
The radius of the circle is 5.
Step 3:
Write the equation of the circle.
The equation of a circle with center (h, k) and radius r is given by:
(x - h)² + (y - k)² = r²
Using the midpoint as the center (h, k) and the radius we calculated:
(x - 2)² + (y - 0)² = 5²
(x - 2)² + y² = 25
Therefore,
The equation of the circle with diameter AB and endpoints A(5, 4) and B(-1, -4) is (x - 2)² + y² = 25.
Learn more about Circle here:
https://brainly.com/question/11833983
#SPJ4
In a completely randomized experimental design, three brands of paper towels were tested for their ability to absorb water. Equal-size towels were used, with four sections of towels tested per brand. The absorbency rating data follow. At a level of significance, does there appear to be a difference in the ability of the brands to absorb water?
Answer:
Yes. At this significance level, there is evidence to support the claim that there is a difference in the ability of the brands to absorb water.
Step-by-step explanation:
The question is incomplete:
The significance level is 0.05.
The data is:
Brand X: 91, 100, 88, 89
Brand Y: 99, 96, 94, 99
Brand Z: 83, 88, 89, 76
We have to check if there is a significant difference between the absorbency rating of each brand.
Null hypothesis: all means are equal
[tex]H_0:\mu_x=\mu_y=\mu_z[/tex]
Alternative hypothesis: the means are not equal
[tex]H_a: \mu_x\neq\mu_y\neq\mu_z[/tex]
We have to apply a one-way ANOVA
We start by calculating the standard deviation for each brand:
[tex]s_x^2=30,\,\,s_y^2=6,\,\,s_z^2=35.33[/tex]
Then, we calculate the mean standard error (MSE):
[tex]MSE=(\sum s_i^2)/a=(30+6+35.33)/3=71.33/3=23.78[/tex]
Now, we calculate the mean square between (MSB), but we previously have to know the sample means and the mean of the sample means:
[tex]M_x=92,\,\,M_y=97,\,\,M_z=84\\\\M=(92+97+84)/3=91[/tex]
The MSB is then:
[tex]s^2=\dfrac{\sum(M_i-M)^2}{N-1}\\\\\\s^2=\dfrac{(92-91)^2+(97-91)^2+(84-91)^2}{3-1}\\\\\\s^2=\dfrac{1+36+49}{2}=\dfrac{86}{2}=43\\\\\\\\MSB=ns^2=4*43=172[/tex]
Now we calculate the F statistic as:
[tex]F=MSB/MSE=172/23.78=7.23[/tex]
The degrees of freedom of the numerator are:
[tex]dfn=a-1=3-1=2[/tex]
The degrees of freedom of the denominator are:
[tex]dfd=N-a=3*4-3=12-3=9[/tex]
The P-value of F=7.23, dfn=2 and dfd=9 is:
[tex]P-value=P(F>7.23)=0.01342[/tex]
As the P-value (0.013) is smaller than the significance level (0.05), the null hypothesis is rejected.
There is evidence to support the claim that there is a difference in the ability of the brands to absorb water.
Dot Products of Vectors
Quiz
Active
Find a b if a = 10i + 4j and b = 3i + 4%.
a. (30,16)
c. 46
b. -14
d. (13,8)
Answer:
choice c. 46
Step-by-step explanation:
Find a b if a = 10i + 4j and b = 3i + 4%
a = <10, 4>
b = <3, 4>
a*b = <10, 4> * <3, 4> = 10*3 + 4*4 = 30 + 16 = 46
Answer:
C. 46
Step-by-step explanation:
T(t)T, models the daily high temperature (in Celsius) in Santiago, Chile, t days after the hottest day of the year. Here, t is entered in radians.
T(t)=7.5cos(2π/365t)+21.5
What is the second time after the hottest day of the year that the daily high temperature is 20 degrees celsius?
Round your final answer to the nearest whole day.
Answer:
the answer is 262 days
Step-by-step explanation:
To find the second time after the hottest day of the year that the daily high temperature is 20 degrees Celsius, you need to solve the equation T(t) = 20. This involves finding the inverse cosine of a specific value, setting up an equation, and adding one year to the solution. After performing these steps, you can find the value of t that corresponds to the second time.
Explanation:To find the second time after the hottest day of the year that the daily high temperature is 20 degrees Celsius, we need to solve the equation T(t) = 20. We can rewrite this equation as 7.5cos(2π/365t) + 21.5 = 20. Subtracting 21.5 from both sides gives us 7.5cos(2π/365t) = -1.5. Dividing both sides by 7.5 and simplifying further, we have cos(2π/365t) = -0.2. To find the second time, we need to find the value of t that satisfies this equation.
To find the value of t, we need to use the inverse cosine function (also known as arccosine). The inverse cosine function (cos^(-1)) gives us the angle whose cosine is a specific value. In this case, we want to find t such that cos(2π/365t) = -0.2. We can use a calculator or math software to find the inverse cosine of -0.2. Let's assume the inverse cosine of -0.2 is x.
Now we can set up an equation: 2π/365t = x. Solving for t, we get t = (365x)/(2π). However, we need to find the second time after the hottest day, so we need to find the value of t that satisfies the equation after adding one year (365 days) to the original value. Therefore, the second time after the hottest day of the year that the daily high temperature is 20 degrees Celsius is t = (365x)/(2π) + 365.
Heights (cm) and weights (kg) are measured for 100 randomly selected adult males, and range from heights of 138 to 190 cm and weights of 39 to 150 kg. Let the predictor variable x be the first variable given. The 100 paired measurements yield x overbarequals167.46 cm, y overbarequals81.44 kg, requals0.108, P-valueequals0.285, and ModifyingAbove y with caretequalsnegative 105plus1.08x. Find the best predicted value of ModifyingAbove y with caret (weight) given an adult male who is 177 cm tall. Use a 0.05 significance level.
Answer:
Best predicted value of y' = 86.16 kg
Step-by-step explanation:
Given,
n = 100
Range of heights = 138 - 190cm
Range of weight = 39 to 150 kg
x' =167.46 cm
y' = 81.44 kg
r = 0.108
p value = 0.285
y = - 105 + 1.08x
Significance level = 0.05
We reject H0 since pvalue, 0.285 is less than significance level of 0.05.
Therefore,
Given height of adult male, x = 177 cm
y = - 105 + 1.08x
The best predicted value of y' =
y' = - 105 + 1.08(177)
y' = 86.16 kg
The best predicted value of y' is 86.16kg
Plz help will choose brainliest!
Answer:
D, E, F
Step-by-step explanation:
The first step I would do is distribute the original equation. After distributing, the equation is now 8x² + 16xy. The first answer I see that matches this is D.
Then, after already eliminating A, B, and C, I look at E. I distribute the x and find out it is also equal to 8x² + 16xy.
Then, I look at F. After distributing again, it is also equal to 8x² + 16xy.
what is the difference between distrust and distake .
Answer:
The difference between mistrust and distrust comes down to nuances in meaning. Distrust is a withholding of trust based on evidence or informed opinion. Many people distrust salespeople working on commission, for instance, knowing that these salespeople personally benefit from their purchases.
Step-by-step explanation:
A consumer research group is interested in testing an automobile manufacturer's claim that a new economy model will travel at least 27 miles per gallon of gasoline (H 0: 27). With a .02 level of significance and a sample of 40 cars, what is the rejection rule based on the value of for the test to determine whether the manufacturer's claim should be rejected (to 2 decimals)? Assume that is 6 miles per gallon.
Answer:
The alternative hypothesis H0, should be rejected, if sample mean, X' < 25.051
Step-by-step explanation:
Given:
Sample size, n = 40
Mean, μ = 27
Significance level = 0.02
Standard deviation = 6
For null hypothesis :
H0 : μ ≥ 27
For alternative hypothesis :
H1 : μ < 27
At significance level, α = 0.02, from Z table, Zα = 2.054
This is a left tailed test
Solving for X' we have:
[tex] X' = u - Za \frac{\sigma}{\sqrt{n}}[/tex]
[tex] X' = 27 - 2.054 \frac{6}{\sqrt{40}}= 25.051[/tex]
The alternative hypothesis H0, should be rejected, if sample mean, X' < 25.051
The rejection rule is based on the value of for the test to determine whether the manufacturer's claim should be rejected is [tex]\mu<27[/tex].
Given :
The sample size is 40..02 level of significance.The mean is 27.The standard deviation is 6.The following steps can be used in order to determine the rejection rule based on the value of the test:
Step 1 - The Hypothesis test can be used in order to determine the rejection rule based on the value of the test.
The null hypothesis is given below:
[tex]H_0 : \mu\geq 27[/tex]
The alternate hypothesis is given below:
[tex]H_a : \mu<27[/tex]
Step 2 - Now, the formula of X' is given below:
[tex]X' = \mu-Z_\alpha \dfrac{\sigma}{\sqrt{n} }[/tex]
Step 3 - Now, substitute the values of the known terms in the above formula.
[tex]X' = 27-2.054 \dfrac{6}{\sqrt{40} }[/tex]
Step 4 - SImplify the above expression.
[tex]X' = 25.051[/tex]
From the above steps, it can be concluded that the null hypothesis is rejected.
For more information, refer to the link given below:
https://brainly.com/question/10758924
Use the information in the table to find the constant of
proportionality and write the equation.
The constant of proportionality is
The equation that represents this proportional
relationship is
N
5
4
10
6
12.5
Answer:
2.5
and
y=2.5x
Step-by-step explanation:
Answer:
2.5
y=2.5x
Step-by-step explanation:
I hope you do good today I'm a little sad sorry I didn't do the joke of the day :(
What is the area of 6cm and 7cm in square centimeters
Answer:
42cm²
Step-by-step explanation:
b×h
6×7=42
area-To find the area of a rectangle multiply its height by its width. For a square you only need to find the length of one of the sides (as each side is the same length) and then multiply this by itself to find the area.
Answer:
42 sq cm
Step-by-step explanation:
6 x 7=42
There are four entrances to the Government Center Building in downtown Philadelphia. The building maintenance supervisor would like to know if the entrances are equally utilized. To investigate, 401 people were observed entering the building. The number using each entrance is reported below. At the 0.01 significance level, is there a difference in the use of the four entrances? Entrance Frequency Main Street 81
Answer:
Yes. We have evidence to support the claim that there is a difference in the use of the four entrances.
Step-by-step explanation:
The question is incomplete:
Entrance Frequency
Main Street 81
Broad Street 129
Cherry Street 72
Walnut Street 119
Total: 401
The building maintenance supervisor wants to know if the entrances are equally utilized.
This problem can be solved using the Chi-square goodess of fit test.
The expected value for each door is
[tex]E=401/4=100.25[/tex]
The degrees of freedom are equal to the number of categories (4 doors) minus one:
[tex]df=n-1=4-1=3[/tex]
Then, the value of the chi-square statistic can be calculated as:
[tex]\chi^2=\sum \dfrac{(O_i-E)^2}{E}\\\\\\\chi^2=\dfrac{(81-100.25)^2}{100.25}+\dfrac{(129-100.25)^2}{100.25}+\dfrac{(72-100.25)^2}{100.25}+\dfrac{(119-100.25)^2}{100.25}\\\\\\\chi^2=\dfrac{370.5625+826.5625+798.0625+351.5625}{100.25}=\dfrac{2346.75}{100.25}=23.41[/tex]
The P-value for this test statistic χ^2=23.41 and df=3 is:
[tex]P-value=P(\chi^2_3>23.41)=0.00003[/tex]
This P-value is much smaller than the significance level (0.01), so the effect is significant.
We have evidence to support the claim that there is a difference in the use of the four entrances.
g A popular theory is that presidential candidates have an advantage if they are taller than their main opponents. Listed are heights (in centimeters) of randomly selected presidents along with the heights of their main opponents. Complete parts (a) and (b) below. Height (cm )of President 191 180 180 182 197 180 Height (cm )of Main Opponent 166 179 168 183 194 186 a. Use the sample data with a 0.05 significance level to test the claim that for the population of heights for presidents and their main opponents, the differences have a mean greater than 0 cm. In this example, mu Subscript d is the mean value of the differences d for the population of all pairs of data, where each individual difference d is defined as the president's height minus their main opponent's height. What are the null and alternative hypotheses for the hypothesis test?
Answer:
Step-by-step explanation:
Corresponding heights of presidents and height of their main opponents form matched pairs.
The data for the test are the differences between the heights.
μd = the president's height minus their main opponent's height.
President's height. main opp diff
191. 166. 25
180. 179. 1
180. 168. 12
182. 183. - 1
197. 194. 3
180. 186. - 6
Sample mean, xd
= (25 + 1 + 12 - 1 + 3 + 6)/6 = 5.67
xd = 5.67
Standard deviation = √(summation(x - mean)²/n
n = 6
Summation(x - mean)² = (25 - 5.67)^2 + (1 - 5.67)^2 + (12 - 5.67)^2+ (- 1 - 5.67)^2 + (3 - 5.67)^2 + (- 6 - 5.67)^2 = 623.3334
Standard deviation = √(623.3334/6 sd = 10.19
For the null hypothesis
H0: μd ≥ 0
For the alternative hypothesis
H1: μd < 0
The distribution is a students t. Therefore, degree of freedom, df = n - 1 = 6 - 1 = 5
The formula for determining the test statistic is
t = (xd - μd)/(sd/√n)
t = (5.67 - 0)/(10.19/√6)
t = 1.36
We would determine the probability value by using the t test calculator.
p = 0.12
Since alpha, 0.05 < than the p value, 0.12, then we would fail to reject the null hypothesis.
Therefore, at 5% significance level, we can conclude that for the population of heights for presidents and their main opponents, the differences have a mean greater than 0 cm.
The null hypothesis in this case would be that there is no average height advantage for presidents over their main opponents (µd ≤ 0), while the alternative hypothesis is that presidents are taller on average (µd > 0). A paired t-test with a significance level of 0.05 is usually employed in testing these hypotheses using the p-value and t-score.
Explanation:In hypothesis testing, the goal is to determine the validity of a claim made. In this case, the claim is that the mean difference in height, where the difference is calculated as the president's height minus their main opponent's height, is greater than 0 cm. This represents the theory that taller presidential candidates have an advantage.
For setting up a null hypothesis and an alternative hypothesis, we consider the following parameters:
Null Hypothesis (H₀): There is no height advantage for presidents (µd ≤ 0) Alternative Hypothesis (Ha): Presidents are taller on average (µd > 0)
To test these hypotheses, we would typically use a one-sample t-test for paired differences with a significance level (alpha) of 0.05. A p-value less than this would allow us to reject the null hypothesis in favor of the alternative hypothesis that presidents are on average taller than their main opponents. Use of p-value and t-score is essential in conducting such a test.
Learn more about Hypothesis Testing here:https://brainly.com/question/34171008
#SPJ3
The data in the table represents the value of a savings
account at the end of each year for 6 years. The
relationship between the increasing years and the
increasing value of the account is exponential.
There is [ ]
rate of change in an
exponential relationship
After each year, the value of the account is[. ]times as
large as the previous year
First missing either a constant additive, or a constant multiplicative, or no constant
Second missing word either 0.5 or 1.05 or 1.5 or 2
Answer:
The answer is constant multiplicative and it is 1.05 times larger.
There is constant rate of change in an exponential relationship.
The value of the account is 1.05 times.
In the given statement, it states that there is a [ ] rate of change in an exponential relationship. The missing word in this case would be "constant."
In an exponential relationship, the rate of change between consecutive terms is constant.
Now, after each year, the value of the account is [. ] times as large as the previous year. The missing value in this case would be "1.05."
This indicates that the value of the account increases by a factor of 1.05 each year, which corresponds to a 5% annual growth rate.
Learn more about Exponential Relation here:
https://brainly.com/question/29160729
#SPJ2
Blake simplified the expression (StartFraction x Superscript 12 Baseline Over x Superscript negative 3 Baseline EndFraction) Superscript 5 to StartFraction 1 Over x Superscript 20 Baseline EndFraction. What was Blake’s mistake?
Answer:
D.
Step-by-step explanation:
Answer:
D.He divided the exponents in the parentheses instead of subtracting.
Step-by-step explanation:
Edge 2022
What is the perimeter of s triangle with side lengths of 5 cm, 8 cm, and 9 cm?
Answer:
22 cm
Step-by-step explanation:
The perimeter is the distance all the way around a shape. To find the perimeter, add up all the sides
The side lengths are 5, 8 and 9
5+8+9=22
So, the perimeter is 22 centimeters.
Find the value of x.
Answer: 150
Step-by-step explanation: cause it has six side in total of 720 and subtract it and you have 150
g Assume that the distribution of time spent on leisure activities by adults living in household with no young children is normally distributed with a mean of 4.5 hours per day and a standard deviation of 1.3 hours per day. Find the probability that the amount of time spent on leisure activities per day for a randomly selected adult from the population of interest is less than 6 hours per day. Round your answer to four decimal places. (make sure to put a 0 in front of the decimal ie 0.1 vs .1)
Answer:
"The probability that the amount of time spent on leisure activities per day for a randomly selected adult from the population of interest is less than 6 hours per day" is about 0.8749.
Step-by-step explanation:
We have here a random variable that is normally distributed, namely, the time spent on leisure activities by adults living in a household with no young children.
The normal distribution is determined by two parameters: the population mean, [tex] \\ \mu[/tex], and the population standard deviation, [tex] \\ \sigma[/tex]. In this case, the variable follows a normal distribution with parameters [tex] \\ \mu = 4.5[/tex] hours per day and [tex] \\ \sigma = 1.3[/tex] hours per day.
We can solve this question following the next strategy:
Use the cumulative standard normal distribution to find the probability.Find the z-score for the raw score given in the question, that is, x = 6 hours per day.With the z-score at hand, we can find this probability using a table with the values for the cumulative standard normal distribution. This table is called the standard normal table, and it is available on the Internet or in any Statistics books. Of course, we can also find these probabilities using statistics software or spreadsheets.We use the standard normal distribution because we can "transform" any raw score into standardized values, which represent distances from the population mean in standard deviations units, where a positive value indicates that the value is above the mean and a negative value that the value is below it. A standard normal distribution has [tex] \\ \mu = 0[/tex] and [tex] \\ \sigma = 1[/tex].
The formula for the z-scores is as follows
[tex] \\ z = \frac{x - \mu}{\sigma}[/tex] [1]
Solving the question
Using all the previous information and using formula [1], we have
x = 6 hours per day (the raw score).
[tex] \\ \mu = 4.5[/tex] hours per day.
[tex] \\ \sigma = 1.3[/tex] hours per day.
Then (without using units)
[tex] \\ z = \frac{x - \mu}{\sigma}[/tex]
[tex] \\ z = \frac{6 - 4.5}{1.3}[/tex]
[tex] \\ z = \frac{1.5}{1.3}[/tex]
[tex] \\ z = 1.15384 \approx 1.15[/tex]
We round the value of z to two decimals since most standard normal tables only have two decimals for z.
We can observe that z = 1.15, and it tells us that the value is 1.15 standard deviations units above the mean.
With this value for z, we can consult the cumulative standard normal table, and for this z = 1.15, we have a cumulative probability of 0.8749. That is, this table gives us P(z<1.15).
We can describe the procedure of finding this probability in the next way: At the left of the table, we have z = 1.1; we can follow the first line on the table until we find 0.05. With these two values, we can determine the probability obtained above, P(z<1.15) = 0.8749.
Notice that the probability for the z-score, P(z<1.15), of the raw score, P(x<6) are practically the same, [tex] \\ P(z<1.15) \approx P(x<6)[/tex]. For an exact probability, we have to use a z-score = 1.15384 (without rounding), that is, [tex] \\ P(z<1.15384) = P(x<6) = 0.8757[/tex]. However, the probability is approximated since we have to round z = 1.15384 to z = 1.15 because of the use of the table.
Therefore, "the probability that the amount of time spent on leisure activities per day for a randomly selected adult from the population of interest is less than 6 hours per day" is about 0.8749.
We can see this result in the graphs below. First, for P(x<6) in [tex] \\ N(4.5, 1.3)[/tex] (red area), and second, using the standard normal distribution ([tex] \\ N(0, 1)[/tex]), for P(z<1.15), which corresponds with the blue shaded area.
Final answer:
The question seeks to find the probability that an adult spends less than 6 hours per day on leisure activities, using the given mean and standard deviation for a normal distribution. The z-score is calculated and then used to determine the probability using the cumulative normal distribution function.
Explanation:
The student's question asks to find the probability that a randomly selected adult from a certain population spends less than 6 hours per day on leisure activities, given that the distribution of time spent is normally distributed with a mean of 4.5 hours and a standard deviation of 1.3 hours.
To solve this, you can use the z-score formula:
z = (X - μ) / σ
where X is the value of interest (6 hours), μ is the mean (4.5 hours), and σ is the standard deviation (1.3 hours).
Using this, we calculate:
z = (6 - 4.5) / 1.3
= 1.15 / 1.3
= 0.8846
Now, we look up this z-score in a standard normal distribution table or use a calculator with the normal distribution function to find the corresponding probability.
Assuming normal CDF is the function for cumulative normal distribution:
probability = CDF(-∞, 0.8846, 0, 1)
This will give us the probability that the adult spends less than 6 hours per day on leisure activities. Remember, the cumulative distribution function gives the area to the left of the z-score, which corresponds to the probability of obtaining a value less than the one of interest.
What is the base area of the cone?
°15 m2
°25 m2
°45 m2
°125 m2
V=75 m3
h=5m
Answer:
It is 45m2
Step-by-step explanation:
Just took did the question of the topic calculating the Base of Area of a Cone
Answer:
its 42 m^2
Step-by-step explanation: did it on edge
Note: picture not drawn to scale The circle above has a radius of 12 cm. What is the area of the circle? Use = 3.14. A. 75.36 cm2 B. 37.68 cm2 C. 904.32 cm2 D. 452.16 cm2
Answer:
452.16
Step-by-step explanation:
Area of a circle = pi*radius squared
A= 3.14(12)^2
=3.14*144
=452.16
Final answer:
The area of a circle with a radius of 12 cm can be calculated using the formula A = \u03C0r^2. By applying the radius to this formula with pi approximated to 3.14, we obtain an area of 452.16 cm^2, which corresponds to option D.
Explanation:
To calculate the area of the circle with a radius of 12 cm, we use the formula: A = \\u03C0r^2\
Where (pi) is approximately 3.14 and r is the radius of the circle.
Plugging the radius into the formula:
A = 3.14 * (12 cm)^2
A = 3.14 * 144 cm^2
A = 452.16 cm^2
Thus, the correct answer is D. 452.16 cm^2.
Which of these shows a right angle
Answer:
the 1st one
Step-by-step explanation:
What is this expression in simplified form? (-7√3)(11√10)
Answer:
[tex]-77\sqrt{30}[/tex]
Step-by-step explanation:
[tex](-7\sqrt{3})(11\sqrt{10})=-77\sqrt{30}[/tex]
Hope this helps!
The simplified form of the expression is -77√33
Given the surd function (-7√3)(11√10)
Multiply the surd functions together. To do this, you multiply both the integers and the surd functions separately as shown:
(-7*11)(√3*√11)= (-77) √33= -77√33Hence the simplified form of the expression is -77√33
Learn more on surd here: https://brainly.com/question/24372463
Please help me and Katie don’t delete it
Answer:
A.
I say this is the answer because if she has gotten into a habait of buying and breaking glasses,shes just very careless
Answer:
hope she won
t
Step-by-step explanation:
Circle P has a circumference of approximately 75
inches.
What is the approximate length of the radius, r? Use
3.14 for . Round to the nearest inch.
12 inches
24 inches
038 inches
46 inches
Answer:
12 inches
Step-by-step explanation:
c=2*pi*r
75 = 2*3.14*r
r=75/(2*314)=75/6.28=11.9, which is close to 12
Bob ordered 17 yards of lumber to build a treehouse how many inches of lumber did he order
Answer:
six hunddered n twelve
Step-by-step explanation:
Examine the following expression. p squared minus 3 + 3 p minus 8 + p + p cubed Which statements about the expression are true? Check all that apply. The constants, –3 and –8, are like terms. The terms 3 p and p are like terms. The terms in the expression are p squared, negative 3, 3 p, negative 8, p, p cubed. The terms p squared, 3 p, p, and p cubed have variables, so they are like terms. The expression contains six terms. The terms p squared and p cubed are like terms. Like terms have the same variables raised to the same powers. The expression contains seven terms.
Answer:
see the bullet list below
Step-by-step explanation:
Given the expression: p² -3 +3p -8 +p +p³
The following statements are true:
The constants, –3 and –8, are like terms. The terms 3 p and p are like terms. The terms in the expression are p squared, negative 3, 3 p, negative 8, p, p cubed. The expression contains six terms. Like terms have the same variables raised to the same powers._____
Terms are generally separated by + or - signs. (The sign is considered to be part of the term.) In the context of a polynomial, terms may be constants, or may be a product with factors that are constants or variables.
_____
Further comments on "term"
In other contexts, the word "term" is used for various purposes. It can designate a member of a sequence, the left or right side of an equation, the numerator or denominator of a rational expression, or just about any identifiable expression that can be considered as a unit. Whereas "coefficient" or "factor" may apply to just about any subset of the (prime) factors of a product, the word "term" is generally restricted to consideration of the product as a whole.
In the given expression, -3 and -8 are like terms, while 3p and p are also like terms. The expression contains six terms and like terms have the same variables raised to the same powers. However, not all terms with variables are like terms in this instance.
Explanation:The expression given is p squared minus 3 + 3p minus 8 + p + p cubed. When we look into it, we can see a couple of true statements.
The constants, -3 and -8, are indeed considered 'like terms' because both of them are constants without a variable part.The terms 3p and p are like terms because they both have the same variable component 'p' with the power of 1.The expression consists of six different terms.Like terms do have the same variables which are raised to the same powers.However, the terms p squared, 3p, p, and p cubed are not like terms since the powers of p in each term are different. Similarly, the terms p squared and p cubed are not like terms since the powers of p are 2 and 3, which are not the same.
Learn more about Like Terms here:https://brainly.com/question/33652886
#SPJ3
What steps should be taken to calculate the volume of the right triangular prism? Select three options.
A triangular prism. The triangular base has a base of 8 meters and height of 14 meters. The height of the prism is 7 meters.
Use the formula A = one-half b h to find the area of the base.
Use the formula A = b h to find the area of the base.
The area of the base, A, is One-half (7) (8) = 28 meters squared.
The area of the base, A, is One-half (8) (14) = 56 meters squared.
The volume of the prism, V is (56) (7) = 392 meters cubed.
Answer:
A, D, and the choice that says the volume is ~261.33 metres cubed
Step-by-step explanation:
The volume of a triangular prism is denoted by: V = (1/3) * Bh, where B is the base area and h is the height.
Here, we know that the base is a triangle with base 8 and height 14, and the overall height is 7. The first step is to find the area of the base. The area of a triangle is denoted by:
A = (1/2) * b * h, where b is the base and h is the height, so A is correct.
Plug values in:
A = (1/2) * 8 * 14 = 56 metres squared, so the D is correct.
Then use this and the height of 14 to find the volume:
V = (1/3) * Bh
V = (1/3) * 56 * 14 = 784/3 metres cubed (I'm assuming you missed an answer choice when copying the problem on here, so the correct last option is the one that says the volume is 784/3 or ~261.33 metres cubed)
Answer:
Use the formula A = one-half b h to find the area of the base.
The area of the base, A, is One-half (8) (14) = 56 meters squared.
The volume of the prism, V is (56) (7) = 392 meters cubed.
Step-by-step explanation:
Volume of prism:
Base area × height
Base area:
½ × 8 × 14 = 56
Volume:
56 × 7 = 392