Which graph represents the piecewise-defined function f(x) = -1.5x + 3.5, x < 2?
4 + x, x >2
Answers
Answer:
DID IT oN EDGEN UITY
Step-by-step explanation:
The first graph correctly represents our piecewise function f(x) = - 1.5x + 3.5 for x < 2 and 4 + x for x ≥ 2.
What is a piecewise function?A function that is piecewise-defined by numerous subfunctions, each of which has a separate domain interval for which it is applicable.
Piecewise definition is more of an expression of the function than it is a property of the function.
Given a piecewise function f(x) = - 1.5x + 3.5 for x < 2 and 4 + x for x ≥ 2.
Now, strictly less or greater than will be shown as an open circle in the graph and less than or greater than equal to will be shown by a closed circle on the graph.
If we observe the first graph when x = 0, y = 3.5, and the end is represented as an open circle which is < 2 and when x ≥ 2 it is 6 and represented with a closed circle.
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Related Questions
please answer this correctly
Answers
Answer:
557
Step-by-step explanation:
l x w
13x24
13x7
22x7
557
A swimming pool is to be drained. The pool is shaped like a Rectangular prism with length 12m , with 10 m, and depth 3m. Suppose water is pumped out of the pool at a rate of 18 m3 per hour.if the pool starts completely full , how many hours does it take to empty the pool ?
Answers
Answer:
20 hours
Step-by-step explanation:
first calculate volume:
12x10x3=360
then divide by 18
360/18=20
So 20 hours in total
write the equation of the line that is parallel to 2x-y=15 and passes through the point (3,7)
Answers
Answer:
work is shown and pictured
If f(x) = 4–1 and g(x) = 8x, which expression is equivalent to (g-1)(3)?
O 8-3-(4 + 3)
08-3-(4-32
813)-4432
O 6(3) 4-32
Answers
Answer:
Option (3)
Step-by-step explanation:
Given functions are f(x) = 4 - x² and g(x) = 6x
We gave to find the expression for (g - f)(3).
(g - f)(x) = g(x) - f(x)
= 6x - (4 - x²)
= 6x - 4 + x²
By substituting x = 3 in this expression,
(g - f)(x) = 6(3) - 4 + (3)²
Therefore, option (3) will be the answer.
Please answer this correctly
Answers
Answer:
Band: 30%
Chorus: 18%
Painting: 21%
Robotics: 14%
Coding: 17%
A physicist examines 25 water samples for nitrate concentration. The mean nitrate concentration for the sample data is 0.165 cc/cubic meter with a standard deviation of 0.0783. Determine the 80% confidence interval for the population mean nitrate concentration. Assume the population is approximately normal. Step 1 of 2 : Find the critical value that should be used in constructing the confidence interval. Round your answer to three decimal places.
Answers
Answer:
The 80% confidence interval for the the population mean nitrate concentration is (0.144, 0.186).
Critical value t=1.318
Step-by-step explanation:
We have to calculate a 80% confidence interval for the mean.
The population standard deviation is not known, so we have to estimate it from the sample standard deviation and use a t-students distribution to calculate the critical value.
The sample mean is M=0.165.
The sample size is N=25.
When σ is not known, s divided by the square root of N is used as an estimate of σM:
[tex]s_M=\dfrac{s}{\sqrt{N}}=\dfrac{0.078}{\sqrt{25}}=\dfrac{0.078}{5}=0.016[/tex]
The degrees of freedom for this sample size are:
[tex]df=n-1=25-1=24[/tex]
The t-value for a 80% confidence interval and 24 degrees of freedom is t=1.318.
The margin of error (MOE) can be calculated as:
[tex]MOE=t\cdot s_M=1.318 \cdot 0.016=0.021[/tex]
Then, the lower and upper bounds of the confidence interval are:
[tex]LL=M-t \cdot s_M = 0.165-0.021=0.144\\\\UL=M+t \cdot s_M = 0.165+0.021=0.186[/tex]
The 80% confidence interval for the population mean nitrate concentration is (0.144, 0.186).
Which cosine function has maximum of 0.5, a minimum of -0.5, and a period of 2(pi)/3
Answers
Answer:
The answer is "[tex]\bold{y=0.5 \cos 3 \theta}[/tex]"
Step-by-step explanation:
The choices were missing the question so the answer to this question can be defined as follows:
The answer is [tex]y= 0.5 \cos 3\theta[/tex] because:
[tex]\Rightarrow -1 \leq \cos 3 \theta \leq 1\\\\\Rightarrow -0.5 \leq \cos 3 \theta \leq 0.5\\[/tex]
So, the maximum value is = 0.5 and the minimum value is = -0.5 of [tex]\frac{2\pi}{3}[/tex].
Answer:
D. y= 0.5 cos 3 theta
Step-by-step explanation:
Please answer this correctly without making mistakes
Answers
Answer:
589
Step-by-step explanation:
l x w
19x11
5x31
5x45
589
Answer:
589 is the answer
Car engine needs ______________ to avoid friction.
a) water
b) smooth surface
c) oil
d) air
Answers
Answer:
Oil
Step-by-step explanation:
Car engine needs oil to avoid friction.
Answer:
[tex]oil \\ [/tex]
Answer C is correct
Step-by-step explanation:
car engine needs oil to avoid the friction .
hope this helps
brainliest appreciated
good luck! have a nice day!
Use the quadratic formula to find both solutions to the quadratic equation given below. 2x^2+3x-5=0
Answers
Answer:
[tex] x =\frac{-b \pm \sqrt{b^2 -4ac}}{2a}[/tex]
Where a = 2 , b= 3, c= -5, replacing we have this:
[tex]x =\frac{-3 \pm \sqrt{(-3)^2 -4(2)(-5)}}{2*2}[/tex]
And simplifying we got:
[tex] x = \frac{-3 \pm \sqrt{49}}{4}[/tex]
And the two solutions are:
[tex] x_1 = \frac{-3+7}{4}= 1[/tex]
[tex] x_2 = \frac{-3-7}{4}= -\frac{5}{2}[/tex]
And the correct options are:
B and C
Step-by-step explanation:
We have the following equation given:
[tex] 2x^2 +3x -5=0[/tex]
And if we use the quadratic formula given by:
[tex] x =\frac{-b \pm \sqrt{b^2 -4ac}}{2a}[/tex]
Where a = 2 , b= 3, c= -5, replacing we have this:
[tex]x =\frac{-3 \pm \sqrt{(-3)^2 -4(2)(-5)}}{2*2}[/tex]
And simplifying we got:
[tex] x = \frac{-3 \pm \sqrt{49}}{4}[/tex]
And the two solutions are:
[tex] x_1 = \frac{-3+7}{4}= 1[/tex]
[tex] x_2 = \frac{-3-7}{4}= -\frac{5}{2}[/tex]
And the correct options are:
B and C
Answer:
B and C
Step-by-step explanation:
Please help me i need the answer if i knew it i will complete all of them by my self (: .
Answers
10 x 10 = 100
The right answer is 100 units^2
please see the attached picture for full solution
Hope it helps
Good luck on your assignment,
TIMED PLEASE HELP When f = 2 and g = 8, n = 4. If n varies jointly with f and g, what is the constant of variation?
1/4
1/2
4
64
Answers
The Answer is 1/4
Step-by-step explanation:
The required constant of variation for given data is k = 1/4
The correct option is (a)
What is constant of variation?In a direct variation, the product of two variables; in an inverse variation, the ratio of two variables, is called constant of variation
Formula:
k = [tex]\frac{n}{fg}[/tex]
How calculate constant of variation?Here we have given that n = 4, f = 2 and g = 8
Substitute the given values into above formula
k = [tex]\frac{4}{2(8)} =\frac{1}{4}[/tex]
The required constant of variation is 1/4
Therefore the correct option is (a)
This is the conclusion to the answer.
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The percent, X , of shrinkage o n drying for a certain type of plastic clay has an average shrinkage percentage :, where parameter : is unknown. A random sample of 45 specimens from this clay showed an average shrinking percentage of 18.4 and a standard deviation of 2.2.
Required:
a. Estimate at 5% level of significance whether the true average shrinkage percentage U: is greater than 17.5 and write your conclusion.
b. Report the p-value.
Answers
Answer:
a) [tex]t=\frac{18.4-17.5}{\frac{2.2}{\sqrt{45}}}=2.744[/tex]
The degrees of freedom are given by:
[tex]df=n-1=45-1=44[/tex]
The critical value for this case is [tex]t_{\alpha}=1.68[/tex] since the calculated value is higher than the critical we have enough evidence to reject the null hypothesis and we can conclude that the true mean is significantly higher than 18.4
b) [tex]p_v =P(t_{(44)}>2.744)=0.0044[/tex]
Step-by-step explanation:
Information given
[tex]\bar X=18.4[/tex] represent the sample mean
[tex]s=2.2[/tex] represent the sample standard deviation
[tex]n=45[/tex] sample size
[tex]\mu_o =17.5[/tex] represent the value to verify
[tex]\alpha=0.05[/tex] represent the significance level
t would represent the statistic
[tex]p_v[/tex] represent the p value
Part a
We want to test if the true mean is higher than 17.5, the system of hypothesis would be:
Null hypothesis:[tex]\mu \leq 17.5[/tex]
Alternative hypothesis:[tex]\mu > 17.5[/tex]
The statistic is given by:
[tex]t=\frac{\bar X-\mu_o}{\frac{s}{\sqrt{n}}}[/tex] (1)
And replacing we got:
[tex]t=\frac{18.4-17.5}{\frac{2.2}{\sqrt{45}}}=2.744[/tex]
The degrees of freedom are given by:
[tex]df=n-1=45-1=44[/tex]
The critical value for this case is [tex]t_{\alpha}=1.68[/tex] since the calculated value is higher than the critical we have enough evidence to reject the null hypothesis and we can conclude that the true mean is significantly higher than 18.4
Part b
The p value would be given by:
[tex]p_v =P(t_{(44)}>2.744)=0.0044[/tex]
A state end-of-grade exam in American History is a multiple-choice test that has 50 questions with 4 answer choices for each question. A student must get at least 25 correct to pass the test, and the questions are very difficult. Question 1. If a student guesses on every question, what is the probability the student will pass
Answers
Answer:
0.004% probability the student will pass
Step-by-step explanation:
I am going to use the normal approximation to the binomial to solve this question.
Binomial probability distribution
Probability of exactly x sucesses on n repeated trials, with p probability.
Can be approximated to a normal distribution, using the expected value and the standard deviation.
The expected value of the binomial distribution is:
[tex]E(X) = np[/tex]
The standard deviation of the binomial distribution is:
[tex]\sqrt{V(X)} = \sqrt{np(1-p)}[/tex]
Normal probability distribution
Problems of normally distributed samples can be solved using the z-score formula.
In a set with mean [tex]\mu[/tex] and standard deviation [tex]\sigma[/tex], the zscore of a measure X is given by:
[tex]Z = \frac{X - \mu}{\sigma}[/tex]
The Z-score measures how many standard deviations the measure is from the mean. After finding the Z-score, we look at the z-score table and find the p-value associated with this z-score. This p-value is the probability that the value of the measure is smaller than X, that is, the percentile of X. Subtracting 1 by the pvalue, we get the probability that the value of the measure is greater than X.
When we are approximating a binomial distribution to a normal one, we have that [tex]\mu = E(X)[/tex], [tex]\sigma = \sqrt{V(X)}[/tex].
In this problem, we have that:
[tex]n = 50, p = \frac{1}{4} = 0.25[/tex]
So
[tex]\mu = E(X) = np = 50*0.25 = 12.5[/tex]
[tex]\sigma = \sqrt{V(X)} = \sqrt{np(1-p)} = \sqrt{50*0.25*0.75} = 3.06[/tex]
If a student guesses on every question, what is the probability the student will pass
Using continuity correction, this is [tex]P(X \geq 25 - 0.5) = P(X \geq 24.5)[/tex], which is 1 subtracted by the pvalue of Z when X = 24.5. So
[tex]Z = \frac{X - \mu}{\sigma}[/tex]
[tex]Z = \frac{24.5 - 12.5}{3.06}[/tex]
[tex]Z = 3.92[/tex]
[tex]Z = 3.92[/tex] has a pvalue of 0.99996
1 - 0.99996 = 0.00004
0.004% probability the student will pass
In 2014, 2.756 billion dollars of e-cigarettes were sold worldwide. Fill in the table with the 2014 sales amount written in millions of dollars.
Answers
Answer:
$2756 million
Step-by-step explanation:
2.756×10⁹ = 2756×10⁶
Sales in 2014 were $2756 million.
_____
Comment on the question
In the US, a billion is 1000 million. In some other parts of the world, a billion is a million million. This sort of question can be ambiguous.
Pls help me with this
Answers
Answer:
x = 1.5
Step-by-step explanation:
Given
[tex]\frac{x}{2} \geq 0.75[/tex]
[tex]\frac{x}{2} < 2.5[/tex]
Required
Find the value of x.
First, the inequalities need to be rewritten and merged;
if [tex]\frac{x}{2} \geq 0.75[/tex], then
[tex]0.75 \leq \frac{x}{2}[/tex]
Multiply both sides by 2
[tex]2 * 0.75 \leq \frac{x}{2} * 2[/tex]
[tex]1.5 \leq x[/tex]
Similarly;
[tex]\frac{x}{2} < 2.5[/tex]
Multiply both sides by 2
[tex]2 * \frac{x}{2} < 2.5 * 2[/tex]
[tex]x < 5[/tex]
Merging these results together; to give
[tex]1.5 \leq x < 5[/tex]
This means that the range of values of x is from 1.5 to 4.9999....
From the question, x is the smallest rational number; from the range above ([tex]1.5 \leq x < 5[/tex]), the minimum value of x is 1.5 and 1.5 is a rational number;
Hence, x = 1.5
Captain Jessica has a ship, the H.M.S. Khan. The ship is two furlongs from the dread pirate Michael and his merciless band of thieves.
The Captain has probability \dfrac{1}{2}
2
1
start fraction, 1, divided by, 2, end fraction of hitting the pirate ship. The pirate only has one good eye, so he hits the Captain's ship with probability \dfrac{1}{6}
6
1
start fraction, 1, divided by, 6, end fraction.
If both fire their cannons at the same time, what is the probability that both the pirate and the Captain hit each other's ships?
Answers
Answer:
[tex]\dfrac{1}{12}[/tex]
Step-by-step explanation:
Probability of the captain hitting the pirate ship [tex]=\dfrac{1}{2}[/tex]
Probability of the pirate hitting the captain's ship [tex]=\dfrac{1}{6}[/tex]
If both fire cannons at the same time, the probability that both the pirate and the captain hit each other's ship
=P(Captain Hits AND Pirate Hits)
=P(Captain Hits) X P(Pirate Hits)
[tex]=\dfrac{1}{2} X \dfrac{1}{6}\\\\=\dfrac{1}{12}[/tex]
Please answer this correctly
Answers
Answer:
pic wont load
Step-by-step explanation:
Answer:
The quarter circle's area is 38.47 yard²
Step-by-step explanation:
The area of a full circle is pi * r ²
The area of a quarter circle is 1/4 * pi * r ²
Given:
Use 3.14 for pi
Round to the nearest hundredths.
Perimeter of quarter circle is 24.99 yards
For r you must leave it as 'r' because we do not know it for now...
1. Circumference of a full circle = 2* pi * r
2. 1/4 * ( 2 * pi * r )
1/4 * ( 2 * 3.14 * r )
1/2 * 3.14 * r
1.57 * r
3 Since r = 'r'
We have to 2 sides running from the centre of the 'pie' to the left and right of the quarter circle which both have a length of exactly 'r'. So you just add 2 * r.
4. The outcome of step 2 + step 3 is the perimeter of quarter circle, which was given as 24.99 inch
1.57 * r + 2 * r = 24.99
( 1.57 + 2 ) * r = 24.99
3.57 * r = 24.99
Divide left and right of the = sign by 3.57
3.57 / 3.57 * r = 24.99 / 3.57
1 * r = 24.99 / 3.57
r = 7
The area of a quarter circle is 1/4 * pi * r ²
1/4 * pi * 7²
1/4 * 49 * pi
49/4 * pi
49/4 * 3.14
38.465
Round to the nearest hundredths gives 38.47 yard²
The quarter circle's area is 38.47 yard²
3. Which of the following values is not possible in probability?
A. P(x) = 1
B. x P(x) = 3 C. P(x) = 0.5
D. P(x) = -0.5
Answers
Answer:
D . P(x)=-0.5
Step-by-step explanation:
i think please mark my answer as a brainliest answer and follow me.
A thermometer shows a temperature of Negative 20 and three-fourths degrees. A chemist recorded this temperature in her notebook using a decimal. Which number did the chemist write in the notebook?
Answers
Answer:
20.75
Step-by-step explanation:
Answer:
C. -20.75
Step-by-step explanation:
9. The mean is defined as the
A. number that shows up most often in a data set.
B. average of a data set.
C. middle of the data set.
D. range of the data set.
Answers
Answer:
B. Average of the data set
Step-by-step explanation:
The mean is defined as the average of a data set and it's formula is
Mean = [tex]\frac{sum of observations}{number of observations}[/tex]
Bonita said that the product of 5/6 x 1 2/3 is 7/3.
How can you tell that her answer is wrong.
Answers
Answer:
Bonita's product is too large
Step-by-step explanation:
The two factors in the problem are (5/6) and (5/3). The factor 5/6 is less than 1, ensuring that the product will be less than 5/3.
Bonita's result of 7/3 is more than 5/3, so is too large to be the product.
A shareholders' group, in lodging a protest, claimed that the mean tenure for a chief executive office (CEO) was at least eight years. A survey of companies reported in the Wall Street Journal found a sample mean tenure x = 7.56 of years for CEOs with a standard deviation of years s = 6.67 years.
A. Formulate hypotheses that can be used to challenge the validity of the claim made by the shareholders' group.
B. Assume 70 companies were included in the sample. What is the p-value for your hypothesis test?
C. At α = 0.02, what is your conclusion?
Answers
Answer:
could be c might be a also
Step-by-step explanation:
What is the equation of the line that passes through (4, 2) ) and is parallel to 3x - 2y = - 6 ?
Answers
Answer:
[tex]y=\frac{3}{2} x-4[/tex]
Step-by-step explanation:
The graph I provided shows it passes thru (4,2) and that it is parallel
Answer:
y = 3/2x -4
Step-by-step explanation:
3x - 2y = - 6
First find the slope by putting it in slope intercept form
Subtract 3x from each side
-2y = -3x-6
Divide by -2
y = -3x/-2 -6/-2
y = 3/2x +3
The slope is 3/2
Parallel lines have the same slope
We have the slope 3/2 and a point (4,2)
y = mx+b where m is the slope and b is the y intercept
y =3/2x+b
Substitute the point into the equation
2 = 3/2(4) +b
2 = 6 +b
Subtract 6
2-6 = 6-6+b
-4 =b
y = 3/2x -4
Erin has previously recorded all credit card activity manually using the Expense transaction screen and reconciled the account using the Reconciliation Tool. After connecting her credit card in the Banking Center, she doesn’t see any matches for the transactions she previously entered and reconciled.
Answers
Answer:
The steps Erin has to take for the reconciliation of her account and activities is as follows: Select the reconciled transactions, Select Batch actions, and Modify the selected ones.
Step-by-step explanation:
Solution
Since Erin could not detect any matches for the transactions she has entered before and enrolled, she needs to take the following processes to reconcile back all her credit activities which is stated below:
Process 1 :Select the reconciled transactions
Process 2 :Batch Actions
Process 3: Modify Selected
From the process stated above Erin can first of all choose the reconciled transactions, after that she can select the batch actions and lastly modify the ones that was selected with the aim of putting or adding them back in the account reconciliation.
Listed below are head injury measurements from small cars that were tested in crashes. The measurements are in "hic," which is a measurement of a standard "head injury criterion," (lower "hic" values correspond to safer cars). The listed values correspond to cars A, B, C, D, E, F, and G, respectively. Find the
a. mean,
b. median,
c. midrange,
d. mode for the data.
Also complete parts e. and f. 514 541 302 400 507 406 369
Answers
The question is incomplete! Complete question along with answer and step by step explanation is provided below.
Question:
Listed below are head injury measurements from small cars that were tested in crashes. The measurements are in "hic," which is a measurement of a standard "head injury criterion," (lower "hic" values correspond to safer cars). The listed values correspond to cars A, B, C, D, E, F, and G, respectively.
514 541 302 400 507 406 369
Find the
a. mean,
b. median,
c. midrange,
d. mode for the data.
Also complete parts e. and f.
e. Which car appears to be the safest?
f. Based on these limited results, do small cars appear to have about the same risk of head injury in a crash?
Answer:
a) Mean = 434.14
b) Median = 406
c) Midrange = 421.5
d) Mode = 0
e) Car C appears to be the safest
f) The small cars does not appear to have about the same risk of head injury in a crash.
Step-by-step explanation:
We are given the head injury measurements from small cars that were tested in crashes.
The measurements are in "hic," which is a measurement of a standard "head injury criterion.
The listed values are;
A = 514
B = 541
C = 302
D = 400
E = 507
F = 406
G = 369
a) Mean
The mean of the measurements is given by
Mean = Sum of measurements/ Number of measurements
Mean = (514 + 541 + 302 + 400 + 507 + 406 + 369)/7
Mean = 3039/7
Mean = 434.14
b) Median
Arrange the measurements in ascending order (low to high)
302, 369, 400, 406, 507, 514, 541
The median is given by
Median = (n + 1)/2
Median = (7 + 1)/2
Median = 8/2
Median = 4th
Therefore, the 4th measurement is the median that is 406
Median = 406
c) Mid-range
The midrange is given by
Midrange = (Max + Min)/2
The maximum measurement in the data set is 541
The minimum measurement in the data set is 302
Midrange = (541 + 302)/2
Midrange = 843/2
Midrange = 421.5
d) Mode for the data
The mode of the data set is the most repeated measurement.
302, 369, 400, 406, 507, 514, 541
In the given data set we don't have any repeated measurement therefore, there is no mode or we can say the mode of this data set is 0.
Mode = 0
e) Which car appears to be the safest?
Since we are given that the measurements are in "hic," which is a measurement of a standard "head injury criterion," (lower "hic" values correspond to safer cars)
The lowest hic value corresponds to car C that is 302
Therefore, car C appears to be the safest among other cars.
f) Based on these limited results, do small cars appear to have about the same risk of head injury in a crash?
302, 369, 400, 406, 507, 514, 541
As you can notice, the hic values differ a lot from each other therefore, we can conclude that the small cars does not appear to have about the same risk of head injury in a crash.
2 number cubes are rolled
what is the probability that the first lands on an odd number and the second lands on an even number?
Answers
Answer:
1/4
Step-by-step explanation:
1/2 times 1/2
1/2 because there is 3 odds and 3 evens
the total is 6
3/6 equals to 1/2
so 1/2 times 1/2 is 1/4
The population of bats in a large cave is 7000 and is growing exponentially at 14% per year. Write a function to represent the population of bats after
tt
t years, where the monthly rate of change can be found from a constant in the function.
Answers
Answer:
y=7000+14^t
Step-by-step explanation:
This equation shows that the original population of bats was 7000 and grows exponentially at a rate of 14% per year.
I put the graph below so you can see it.
In this exercise we have to identify how to write an exponential function from the data informed in the text, in this way we find that:
[tex]y=7000+14^t[/tex]
From the information given in the statement we find that:
The original population of bats was 7000Rate of 14% per year.Then writing this function as:
[tex]y=7000+14^t[/tex]
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g Gravel is being dumped from a conveyor belt at a rate of 10 ft3/min, and its coarseness is such that it forms a pile in the shape of a cone whose base diameter and height are always equal. How fast is the height of the pile increasing when the pile is 6 ft high
Answers
Answer:
0.3537 feet per minute.
Step-by-step explanation:
Gravel is being dumped from a conveyor belt at a rate of 10 ft3/min. Since we are told that the shape formed is a cone, the rate of change of the volume of the cone.
[tex]\dfrac{dV}{dt}=10$ ft^3/min[/tex]
[tex]\text{Volume of a cone}=\dfrac{1}{3}\pi r^2 h[/tex]
If the Base Diameter = Height of the Cone
The radius of the Cone = h/2
Therefore,
[tex]\text{Volume of the cone}=\dfrac{\pi h}{3} (\dfrac{h}{2}) ^2 \\V=\dfrac{\pi h^3}{12}[/tex]
[tex]\text{Rate of Change of the Volume}, \dfrac{dV}{dt}=\dfrac{3\pi h^2}{12}\dfrac{dh}{dt}[/tex]
Therefore: [tex]\dfrac{3\pi h^2}{12}\dfrac{dh}{dt}=10[/tex]
We want to determine how fast is the height of the pile is increasing when the pile is 6 feet high.
[tex]When h=6$ feet$\\\dfrac{3\pi *6^2}{12}\dfrac{dh}{dt}=10\\9\pi \dfrac{dh}{dt}=10\\ \dfrac{dh}{dt}= \dfrac{10}{9\pi}\\ \dfrac{dh}{dt}=0.3537$ feet per minute[/tex]
When the pile is 6 feet high, the height of the pile is increasing at a rate of 0.3537 feet per minute.
A supermarket is redesigning it’s checkout lanes. Design A has a sample size of 50, sample mean of 4.1 minutes, and sample standard deviation of 2.2 minutes. Design B has a sample size of 50, sample mean of 3.5 minutes, and sample standard deviation of 1.5 minutes. At the 0.05 level of significance, determine if their is evidence that the checkout times of the two systems differ.
Answers
Answer:
The calculated value t = 1.57736 < 1.9845 at 5 % level of significance
Null hypothesis is accepted at 5 % level of significance
There is no significance difference between Design A and Design B
Step-by-step explanation:
Given sample size of design A
n₁ = 50
sample mean of design A x⁻₁ = 4.1 minutes
Sample standard deviation S₁ = 2.2 minutes
Given sample size of design B
n₂ = 50
sample mean of design A x⁻₂ = 3.5 minutes
Sample standard deviation S₂ = 1.5 minutes
Null Hypothesis : H₀ : There is no significance difference between Design A and Design B
Alternative Hypothesis : H₁:There is significance difference between Design A and Design B
Level of significance ∝ = 0.05
Test statistic
[tex]t = \frac{x^{-} _{1}- x^{-} _{2} }{\sqrt{S^{2} (\frac{1}{n_{1} }+\frac{1}{n_{2} }) } }[/tex]
where
[tex]S^{2} = \frac{n_{1} S_{1} ^{2} +n_{2} S^2_{2} }{n_{1} +n_{2} -2}[/tex]
[tex]S^{2} = \frac{50 (2.2)^{2} +50(1.5)^2}{50+50-2}[/tex]
On calculation , we get
S² = 3.6173
Test statistic
[tex]t = \frac{4.1-3.5}{\sqrt{3.617(\frac{1}{50} +\frac{1}{50} }) }[/tex]
On calculation , we get
t = 1.57736
Degrees of freedom
ν = n₁ + n₂ -2 = 50 +50 -2 =98
t₀.₀₂₅ ,₉₈ = 1.9845
The calculated value t = 1.57736 < 1.9845 at 5 % level of significance
null hypothesis is accepted