Answer:
sin x = 0.998
cosx = 0.046
Step-by-step explanation:
Given that:
tan x = 21
where interval of x is [tex][0,\dfrac{\pi}{2}][/tex].
We know that the trigonometric identity for tan x is:
[tex]tan\theta = \dfrac{Perpendicular}{Base}[/tex]
Comparing with:
[tex]tan x = \dfrac{21}{1}[/tex]
Perpendicular = 21 units
Base = 1 unit
As per pythagorean theorem:
[tex]\text{Hypotenuse}^{2} = \text{Base}^{2} + \text{Perpendicular}^{2}\\[/tex]
[tex]\Rightarrow \text{Hypotenuse}^2 = 21^2 +1^2\\\Rightarrow \text{Hypotenuse} = \sqrt{442} = 21.023\ units[/tex]
interval of x is [tex][0,\dfrac{\pi}{2}][/tex] so values of sinx and cosx will be positive because it is first quadrant where values of sine and cosine are positive.
We know that
[tex]sin\theta = \dfrac{Perpendicular}{Hypotenuse}\\cos\theta = \dfrac{Base}{Hypotenuse}[/tex]
So, sine x :
[tex]\Rightarrow sinx =\dfrac{21}{21.023}\\\Rightarrow sinx = 0.998[/tex]
Similarly, value of cos x :
[tex]\Rightarrow cosx =\dfrac{1}{21.023}\\\Rightarrow cosx = 0.046[/tex]
To collect data on the signal strengths in a neighborhood, Briana must drive from house to house
and take readings. She has a graduate student, Henry, to assist her. Briana figures it would take her
12 hours to complete the task working alone, and that it would take Henry 18 hours if he completed
the task by himself.
Answer: Working together, they can complete the task in 7 hours and 12 minutes.
Step-by-step explanation:
Ok, Briana needs 12 hours to complete the task.
Then we can find the ratio of work over time as:
1 task/12hours = 1/12 task per hour.
This means that she can complete 1/12 of the task per hour.
Henry needs 18 hours to complete the task, then his ratio is:
1 task/18 hours = 1/18 task per hour.
This means that he can complete 1/18 of the task in one hour.
If they work together, then the ratios can be added:
R = 1/12 + 1/18 = 18/(12*18) + 12/(18*12) = 30/216
we can reduce it to:
R = 15/108 = 5/36
So, working together, in one hour they can complete 5/36 of the task, now we can find the number of hours needed to complete the task as:
(5/36)*x = 1 task
x = 36/5 hours = 7.2 hours
knowing that an hour is 60 minutes, then 0.2 of an hour is 60*0.2 = 12 minutes.
then x = 7 hours and 12 minutes.
please - i got this wrong so plz help
Answer:
Area = 108 cm^2
Perimeter = 44 cm
Step-by-step explanation:
Area, -->
24 + 30 + 24 + 30 -->
24(2) + 30(2)
48 + 60 = 108 cm^2
108 = area
10 + 12 + 10 + 12, -->
10(2) + 12(2) = 44 cm
44 = perim.
Hope this helps!
Answer:
Step-by-step explanation:
Draw the diagram.
This time put in the only one line for the height. That is only 1 height is 8 cm. That's it.
The base is 6 + 6 = 12 cm.
The slanted line is 10 cm
That's all your diagram should show. It is much clearer without all the clutter.
Now you are ready to do the calculations.
Area
The Area = the base * height.
base = 12
height = 8
Area = 12 * 8 = 96
Perimeter.
In a parallelagram the opposite sides are equal to one another.
One set of sides = 10 + 10 = 20
The other set = 12 + 12 = 24
Both sets = 20 + 24
Both sets = 44
Answer
Area = 96
Perimeter = 44
eight less than fout times a number is less than 56. what are the possible values of that number
Answer:
x<16
Step-by-step explanation:
number n
eight less than four times a number ... 4 x n - 8
is less than 56 ... < 56
4 x n - 8 < 56
4 x n < 56 + 8
4 x n < 64/4
n < 64 / 4
n < 16
Answer:
Step-by-step explanation:
Let the number be x
Four times the number : 4x
Eight less than four times a number: 4x - 8
4x - 8 < 56
Now add 8 to both sides,
4x < 56+8
4x < 64
Divide both sides by 4,
x < 64/4
x < 16
Possible values of number = Value less than 16
Solve for X. Show all work
Answer:
About 11.77 centimeters
Step-by-step explanation:
By law of sines:
[tex]\dfrac{50}{\sin 62}=\dfrac{x}{\sin 12} \\\\\\x=\dfrac{50}{\sin 62}\cdot \sin 12\approx 11.77cm[/tex]
Hope this helps!
anyone please answer this
Answer:
21
Step-by-step explanation:
1/5 of 30 is 6
10% of 30 is 3
3+6=9
30-9=21
which is 7/10
Answer:
Simon has 7/10 of the cakes left.
What is the value of AC?
Answer:
0.637
Step-by-step explanation:
The average value of a whole sinusoidal waveform over one complete cycle is zero as the two halves cancel each other out
The null hypothesis for this ANOVA F test is: the population mean load failures for the three etch times are all different the population mean load failure is lowest for the 15‑second condition and highest for 60‑second condition at least one population mean load failure differs the sample mean load failure is lowest for the 15‑second condition and highest for 60‑second condition the sample mean load failures for the three etch times are all different the population mean load failures for the three etch times are all equal
Answer:
The population mean load failures for the three etch times are all equal
Step-by-step explanation:
For an ANOVA F test, the null hypothesis always assumes that mean which is also the average value of the dependent variable which is continuously are the same/ there is no difference in the means. The alternative is to test against the null and it is always the opposite of the null hypothesis.
A service station has both self-service and full-service islands. On each island, there is a single regular unleaded pump with two hoses. Let X denote the number of hoses being used on the self-service island at a particular time, and let Y denote the number of hoses on the full-service island in use at that time. The joint pmf of X and Y appears in the accompanying tabulation.
Y
p(x,y), 0 1 2
0 .10 .04 .02
x 1 .08 .20 .06
2 .06 .14 .30
a. What is P(X = 1 and = 1)?
b. Compute P(X land Y 1).
c. Give a word description of the event {X t- 0 and Y 0}, and compute the probability of this event
d. Compute the marginal pmf of X and of Y. Using pX(x), what is P(X 5 1)?
e. Are X and Y independent rv's? Explain.
Answer:
Step-by-step explanation:
Y
p(x,y) 0 1 2
0 0.10 0.04 0.02
x 1 0.08 0.2 0.06
2 0.0 0.14 0.30
a) What is P(X = 1 and = 1)
From the table above we have
P(1,1) = 0.2
b) Compute P(X ≤ 1 and Y ≤ 1).
[tex]=p(0,0)+p(0,1)+p(1,0)+p(1,1)\\\\=0.1+0.04+0.08+0.2\\\\=0.42[/tex]
C)
Let A ={X ≠ 0 and Y ≠ 0}
p{X ≠ 0 , Y ≠ 0}
= p(1,1) + p(1,2) + p(2,1) + p(2,2)
= 0.20 + 0.06 + 0.14 + 0.30
=0.7
d) The possible X values are in the figure 0,1,2
[tex]p_x(0)=p(0,0)+p(0,1)+p(0,2)\\\\=0.1+0.04+0.02\\\\=0.16\\\\p_x(1)=p(1,0)+p(1,1)+p(1,2)\\\\=0.08+0.2+0.06\\\\=0.34\\\\p_x(2)=p(2,0)+p(2,1)+p(2,2)\\\\=0.06+0.14+0.3\\\\=0.5[/tex]
The possible Y values are in the figure 0,1,2
[tex]p_y(0)=p(0,0)+p(1,0)+p(2,0)\\\\=0.1+0.08+0.06\\\\=0.24\\\\p_y(1)=p(0,1)+p(1,1)+p(2,1)\\\\=0.04+0.2+0.14\\\\=0.38\\\\p_y(2)=p(0,2)+p(1,2)+p(2,2)\\\\=0.02+0.06+0.3\\\\=0.38[/tex]
So the probability of x ≤ 1 is
[tex]p(x\leq 1)=p_x(0)+p_x(1)\\\\=0.34+0.16\\\\=0.50[/tex]
e) From the table
[tex]p_x(x=1,y=1)=p(1,1)\\\\=0.2\\\\p_x(1)=0.34\\\\p_y(1)=0.38[/tex]
we multiply both together
0.34 x 0.38
=0.1292
Therefore p(1,1) is not equal px(1), py(1)
Hence x and y are not independent it is not equal
Simplify 18 - 2[x + (x - 5)]. 28 - 4 x 8 - 4 x 28 - 2 x
Answer:
[tex]-4x+28[/tex]
Step-by-step explanation:
[tex]18-2(x+x-5)[/tex]
[tex]18+(-2)(x)+(-2)(x)+(-2)(-5)[/tex]
[tex]18+-2x+-2x+10[/tex]
[tex]-2x-2x+10+18[/tex]
[tex]=-4x+28[/tex]
A student walk 60m on a bearing
of 028 degree and then 180m
due east. How is she from her
starting point, correct to the
nearest whole number?
Answer:
d = 234.6 m
Step-by-step explanation:
You can consider a system of coordinates with its origin at the beginning of the walk of the student.
When she start to walk, she is at (0,0)m. After her first walk, her coordinates are calculated by using the information about the incline and the distance that she traveled:
[tex]x_1=60cos28\°=52.97m\\\\y_1=60sin28\°=28.16m[/tex]
she is at the coordinates (52.97 , 28.16)m.
Next, when she walks 180m to the east, her coordinates are:
(52.97+180 , 28.16)m = (232.97 , 28.16)m
To calculate the distance from the final point of the student to the starting point you use the Pythagoras generalization for the distance between two points:
[tex]d=\sqrt{(x-x_o)^2+(y-y_o)^2}\\\\x=232.97\\\\x_o=0\\\\y=28.16\\\\y_o=0\\\\d=\sqrt{(232.97-0)^2+(28.16-0)^2}m=234.6m[/tex]
The displacement of the student on her complete trajectory was of 234.6m
When planning a more strenuous hike, Nadine figures that she will need at least 0.6 liters of water for each hour on the trail. She also plans to always have at least 1.25 liters of water as a general reserve. If x represents the duration of the hike (in hours) and y represents the amount of water needed (in liters) for a hike, the following inequality describes this relation: y greater or equal than 0.6 x plus 1.25 Which of the following would be a solution to this situation?
Answer:
The solution for this is:
y = (0.6 * x) + 1.25
Hope it helps! :)
Answer:
Having 3.2 liters of water for 3 hours of hiking
Step-by-step explanation:
If x represents the number of hours and y represents the number of liters of water, then we can plug the possible solutions into our inequality to see which solution(s) work.
The first option is having 3 liters of water for 3.5 hours of hiking. We will plug 3 in for y and 3.5 in for x:
y > 0.6x + 1.25
3 > 0.6(3.5) + 1.25
3 > 3.35
But since 3 is not greater than 3.35, this does not work.
The next option is having 2 liters of water for 2.5 hours of hiking:
2 > 0.6(2.5) + 1.25
2 > 2.75
But 2 is not greater than 2.75, so this does not work.
Option c is having 2.3 liters of water for 2 hours of hiking:
2.3 > 0.6(2) + 1.25
2.3 > 2.45
Since 2.3 is not greater than 2.45, this solution does not work.
The last option is having 3.2 liters of water for 3 hours of hiking:
3.2 > 0.6(3) + 1.25
3.2 > 3.05
3.2 IS greater than 3.05, so this solution works!
A manager bought 12 pounds of peanuts for $30. He wants to mix $5 per pound cashews with the peanuts to get a batch of mixed nuts that is worth $4 per pound. How many pounds of cashews are needed
Answer:
18 pounds of cashews are needed.
Step-by-step explanation:
Given;
A manager bought 12 pounds of peanuts for $30.
Price of peanut per pound P = $30/12 = $2.5
Price of cashew per pound C = $5
Price of mixed nut per pound M = $4
Let x represent the proportion of peanut in the mixed nut.
The proportion of cashew will then be y = (1-x), so;
xP + (1-x)C = M
Substituting the values;
x(2.5) + (1-x)5 = 4
2.5x + 5 -5x = 4
2.5x - 5x = 4 -5
-2.5x = -1
x = 1/2.5 = 0.4
Proportion of cashew is;
y = 1-x = 1-0.4 = 0.6
For 12 pounds of peanut the corresponding pounds of cashew needed is;
A = 12/x × y
A = 12/0.4 × 0.6 = 18 pounds
18 pounds of cashews are needed.
In d e f, d f equals 16 and F equal 26. Find Fe to the nearest tenth
Answer:
14.4 units
Step-by-step explanation:
In Trigonometry
[tex]\cos \theta =\frac{Adjacent}{Hypotenuse}\\[/tex]
In Triangle DEF,
[tex]\cos F =\dfrac{EF}{DF}\\\cos 26^\circ =\dfrac{EF}{16}\\EF=16 \times \cos 26^\circ\\=14.4$ units (correct to the nearest tenth).[/tex]
How do you determine the vertex from the vertex from of a quadratic equation
Answer:
it it the highest or lowest point of a parabola
In the fall semester of 2009, the average Graduate Management Admission Test (GMAT) of the students at a certain university was 500 with a standard deviation of 90. In the fall of 2010, the average GMAT was 570 with a standard deviation of 85.5. Which year's GMAT scores show a more dispersed distribution
Answer:
Due to the higher coefficient of variation, 2009's GMAT scores show a more dispersed distribution
Step-by-step explanation:
To verify how dispersed a distribution is, we find it's coefficient of variation.
Coefficient of variation:
Mean of [tex]\mu[/tex], standard deviation of [tex]\sigma[/tex]. The coefficient is:
[tex]CV = \frac{\sigma}{\mu}[/tex]
Which year's GMAT scores show a more dispersed distribution
Whichever year has the highest coefficient.
2009:
Mean of 500, standard deviation of 90. So
[tex]CV = \frac{90}{500} = 0.18[/tex]
2010:
Mean of 570, standard deviation of 85.5. So
[tex]CV = \frac{85.5}{570} = 0.15[/tex]
Due to the higher coefficient of variation, 2009's GMAT scores show a more dispersed distribution
2009's GMAT scores show a more dispersed distribution.
Given that in 2009: Mean = 500 and standard deviation = 90.
In 2010: Mean = 570 and standard deviation = 85.5.
If the standard deviation is higher then the scores will be more dispersed.
Note that: 90 > 85.5. And 90 corresponds to 2009.
So, 2009's GMAT scores show a more dispersed distribution.
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2ft/sec is how many mph?
Answer:
1.36364
Step-by-step explanation:
I calculated the solution on a calculator
So the answer to 1 d.p is 1.4
insert a digit to make numbers that are divisible by 24 if it is possible 38_36
Answer:
ge
Step-by-step explanation:
ge
The histogram shows the number of miles driven by a sample of automobiles in New York City.
What is the minimum possible number of miles traveled by an automobile included in the histogram?
Answer:
0 miles
Step-by-step explanation:
The computation of the minimum possible number of miles traveled by automobile is shown below:
As we can see that in the given histogram it does not represent any normal value i.e it is not evenly distributed moreover, the normal distribution is symmetric that contains evenly distribution data
But this histogram shows the asymmetric normal distribution that does not have evenly distribution data
Therefore the correct answer is 0 miles
Answer:
2,500
That is your correct answer.
Consider the graph of the line of best fit, y = 0.5x + 1, and the given data points. A graph shows the horizontal axis numbered negative 4 to positive 4 and the vertical axis numbered negative 4 to positive 4. Points show an upward trend. Which is the residual value when x = 2? –2 –1 1 2
Answer
its -1
Step-by-step explanation:
ED 2020 boiiiii
The residual value of the line of the best fit when x = 2 is -1
How to determine the residual value?The equation of the line is given as:
y = 0.5x + 1
When x = 2, we have:
y = 0.5 * 2 + 1
Evaluate
y = 2
The residual is the difference between the actual value and the predicted value.
From the complete graph, the actual value is 1.
So, we have:
Residual = 1 - 2
Evaluate
Residual = -1
Hence, the residual value when x = 2 is -1
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Please answer this correctly
Answer:
6 pizzas
Step-by-step explanation:
At least 10 and fewer than 20 makes it 10-19
So,
10-19 => 6 pizzas
6 pizzas have at least 10 pieces of pepperoni but fewer than 20 pieces of pepperoni.
Please help me or assist me in answering this Thank you 5 2/3 X 6 7/8
Answer: 38 23/24
Step-by-step explanation:
Turn the mixed numbers into improper fractions
5 * 3 = 15
15 + 2 = 17
17/3
————————
6 * 8 = 48
48 + 7 = 55
55/8
————————
Now multiply the improper fractions
17/3 * 55/8
17 * 55 = 935
3 * 8 = 24
Divide 935 by 24 to get the answer as a mixed number.
935 / 24 = 38.95833
0.95833/1 = 23/24
935/24 as a mixed number is 38 23/24
Answer: 119 / 4
Step-by-step explanation:
5 2/3 x 6 7/8
= 17/3 x 6 x 7/8
= 17 x 2 x 7/8
= 17 x 2 x 7/8
= 17 x 7/4
= 119 / 4
Solve the equation x^3 + 2x^2 - 11x -12 = 0
Answer: there are 4 solutions
x = -2
x = -1/2 = -0.500
x =(3-√5)/2= 0.382
x =(3+√5)/2= 2.618
Step-by-step explanation:
HELP HELP HELP PLEASE!!!!!
A party rental company has chairs and tables for rent. The total cost to rent 2 chairs and 3 tables is $31. The total cost to rent 6 chairs and 5 tables is $59
What is the cost to rent each chair and each table?
Answer:
The rental of each chair is $2.75
The rental of each table is $8.5
Step-by-step explanation:
Let's name the unknowns "c" for the cost of each chair rental, and "t" for the cost of each table rental.
Now we can create the equations that represent the statements:
a) "The total cost to rent 2 chairs and 3 tables is $31."
2 c + 3 t = 31
b) "The total cost to rent 6 chairs and 5 tables is $59."
6 c + 5 t = 59
now we have a system of two equations and two unknowns that we proceed to solve via the elimination method by multiplying the first equation we got by "-3" so by adding it term by term to the second equation, we eliminate the variable "c" and solve for "t":
(-3) 2 c + (-3) 3 t = (-3) 31
-6 c - 9 t = -93
6 c + 5 t = 59
both these equations added give:
0 - 4 t = -34
t = 34/4 = 8.5
So each table rental is $8.5
now we find the rental price of a chair by using any of the equations:
2 c + 3 t = 31
2 c + 3 (8.5) = 31
2 c + 25.5 = 31
2 c = 5.5
c = 5.5/2
c = $2.75
A grasshopper sits on the first square of a 1×N board. He can jump over one or two squares and land on the next square. The grasshopper can jump forward or back but he must stay on the board. Find the least number n such that for any N ≥ n the grasshopper can land on each square exactly once.
Answer:
n=N-1
Step-by-step explanation:
You can start by imagining this scenario on a small scale, say 5 squares.
Assuming it starts on the first square, the grasshopper can cover the full 5 squares in 2 ways; either it can jump one square at a time, or it can jump all the way to the end and then backtrack. If it jumps one square at a time, it will take 4 hops to cover all 5 squares. If it jumps two squares at a time and then backtracks, it will take 2 jumps to cover the full 5 squares and then 2 to cover the 2 it missed, which is also 4. It will always be one less than the total amount of squares, since it begins on the first square and must touch the rest exactly once. Therefore, the smallest amount n is N-1. Hope this helps!
The smallest value of n is N-1.
What is a square?Square is a quadrilateral of equal length of sides and each angle of 90°.
Here given that there are 1×N squares i.e. N numbers of squares in one row.
The grasshopper can jump either one square or two squares to land on the next square.
Let's assume the scenario of 5 squares present in a row.
Let the grasshopper starts from the first square,
so the grasshopper can cover the full 5 squares in 2 methods;
one method is that it will jump one square at a time and reach at last square.
another method is it will jump all the squares to the finish and then backtrace.
If the grasshopper jumps one square at a time, it will take 4 jumps to cover all 5 squares.
Similarly, If a grasshopper jumps two squares at a time and then backtrace, it will take 2 jumps to reach the 5th square and then it will jump 1 square and then 2 squares to cover the 2 squares it missed, for which the number jump is also 4.
From the above it is clear that the number of jumps will always be one less than the total number of squares if the grasshopper begins from the first square and touch every square exactly once.
Therefore, the smallest value of n is N-1.
Learn more about squares
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Check all of the points that are solutions to the system of inequalities.
y> 4x + 2
y< 4x + 5
Someone help me ASAP
Answer:
It is only (5,24).
Step-by-step explanation:
You are correct.
Sometimes, check all options means there could be just one option.
Mary is running a marathon which is a total of 26 miles. She is running at a pace of 7.5 miles per hour and
has already run 8 miles. If she stays at the same pace, how much time in hours does she have left?
Answer:
2.4 hours
Step-by-step explanation:
If Mary is running 26 miles at a pace of 7.5 miles per hour, it will take her 3.47 hours to run the full course.
26/7.5 = 3.466666...
If she has run 8 miles, 1.07 hours have passed.
8/7.5 = 1.06666666...
Subtract the total time from the time that has already passed to find the time left.
3.47 - 1.07 = 2.4
Mary has 2.4 hours left.
The top figure in the composite figure is called a . And What is the volume?
Answer:
Triangular Prism
volume 748
According to a report an average person watched 4.55 hours of television per day in 2005. A random sample of 20 people gave the following number of hours of television watched per day for last year. At the 10% significance level, do the data provide sufficient evidence to conclude that the amount of television watched per day last year by the average person differed from that in 2005? 1.0 4.6 5.4 3.7 5.2 1.7 6.1 1.9 7.6 9.1 6.9 5.5 9.0 3.9 2.5 2.4 4.7 4.1 3.7 6.2 a. identify the claim and state and b. find the critical value(s) and identify the rejection region(s), c. find the standardized test statistic Sketch a graph decide whether to reject or fail to reject the null hypothesis, and d. interpret the decision in the context of the original claim. e. Obtain a 95%confidence interval
Answer:
a. The claim is that the amount of television watched per day last year by the average person differed from that in 2005.
b. The critical values are tc=-1.729 and tc=1.729.
The acceptance region is defined by -1.792<t<1.729. See the picture attached.
c. Test statistic t=0.18.
The null hypothesis failed to be rejected.
d. At a significance level of 10%, there is not enough evidence to support the claim that the amount of television watched per day last year by the average person differed from that in 2005.
e. The 95% confidence interval for the mean is (2.29, 7.23).
Step-by-step explanation:
We have a sample of size n=20, which has mean of 4.76 and standard deviation of 5.28.
[tex]M=\dfrac{1}{n}\sum_{i=1}^n\,x_i\\\\\\M=\dfrac{1}{20}(1+4.6+5.4+. . .+6.2)\\\\\\M=\dfrac{95.2}{20}\\\\\\M=4.76\\\\\\s=\dfrac{1}{n-1}\sum_{i=1}^n\,(x_i-M)^2\\\\\\s=\dfrac{1}{19}((1-4.76)^2+(4.6-4.76)^2+(5.4-4.76)^2+. . . +(6.2-4.76)^2)\\\\\\s=\dfrac{100.29}{19}\\\\\\s=5.28\\\\\\[/tex]
a. This is a hypothesis test for the population mean.
The claim is that the amount of television watched per day last year by the average person differed from that in 2005.
Then, the null and alternative hypothesis are:
[tex]H_0: \mu=4.55\\\\H_a:\mu\neq 4.55[/tex]
The significance level is 0.1.
The sample has a size n=20.
The sample mean is M=4.76.
As the standard deviation of the population is not known, we estimate it with the sample standard deviation, that has a value of s=5.28.
The estimated standard error of the mean is computed using the formula:
[tex]s_M=\dfrac{s}{\sqrt{n}}=\dfrac{5.28}{\sqrt{20}}=1.181[/tex]
Then, we can calculate the t-statistic as:
[tex]t=\dfrac{M-\mu}{s/\sqrt{n}}=\dfrac{4.76-4.55}{1.181}=\dfrac{0.21}{1.181}=0.18[/tex]
The degrees of freedom for this sample size are:
[tex]df=n-1=20-1=19[/tex]
The critical value for a level of significance is α=0.10, a two tailed test and 19 degrees of freedom is tc=1.729.
The decision rule is that if the test statistic is above tc=1.729 or below tc=-1.729, the null hypothesis is rejected.
As the test statistic t=0.18 is within the critical values and lies in the acceptance region, the null hypothesis failed to be rejected.
There is not enough evidence to support the claim that the amount of television watched per day last year by the average person differed from that in 2005.
We have to calculate a 95% 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=4.76.
The sample size is N=20.
The standard error is s_M=1.181
The degrees of freedom for this sample size are df=19.
The t-value for a 95% confidence interval and 19 degrees of freedom is t=2.093.
The margin of error (MOE) can be calculated as:
[tex]MOE=t\cdot s_M=2.093 \cdot 1.181=2.47[/tex]
Then, the lower and upper bounds of the confidence interval are:
[tex]LL=M-t \cdot s_M = 4.76-2.47=2.29\\\\UL=M+t \cdot s_M = 4.76+2.47=7.23[/tex]
The 95% confidence interval for the mean is (2.29, 7.23).
I. In the testing of a new production method, 18 employees were selected randomly and asked to try the new method. The sample mean production rate for the 18 employees was 80 parts per hour and the sample standard deviation was 10 parts per hour. Provide 90% confidence intervals for the populations mean production rate for the new method, assuming the population has a normal probability distribution.
Answer:
The 90% confidence interval for the mean production rate fro the new method is (75.9, 84.1).
Step-by-step explanation:
We have to calculate a 90% 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=80.
The sample size is N=18.
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{10}{\sqrt{18}}=\dfrac{10}{4.24}=2.36[/tex]
The degrees of freedom for this sample size are:
[tex]df=n-1=18-1=17[/tex]
The t-value for a 90% confidence interval and 17 degrees of freedom is t=1.74.
The margin of error (MOE) can be calculated as:
[tex]MOE=t\cdot s_M=1.74 \cdot 2.36=4.1[/tex]
Then, the lower and upper bounds of the confidence interval are:
[tex]LL=M-t \cdot s_M = 80-4.1=75.9\\\\UL=M+t \cdot s_M = 80+4.1=84.1[/tex]
The 90% confidence interval for the mean production rate fro the new method is (75.9, 84.1).
Multi step equation a-2+3=-2
Answer:
-3
Step-by-step explanation:
a-2+3=-2
-3 -3
a-2=-5
+2 +2
a=-3
// have a great day //
Answer:
a = -3
Step-by-step explanation:
a - 2 + 3 = -2
Add like terms.
a + 1 = -2
Subtract 1 on both sides.
a = -2 - 1
a = -3
The value of a in the equation is -3.