Answer:
[tex]P(X>12)=P(\frac{X-\mu}{\sigma}>\frac{12-\mu}{\sigma})=P(Z>\frac{12-14}{3})=P(z>-0.67)[/tex]
And we can find this probability with the complement rule and with the normal standard table we got:
[tex]P(z>-0.67)=1-P(z<-0.67)=1-0.2514=0.7486 [/tex]
Step-by-step explanation:
Let X the random variable that represent the components whose lenghts of a population, and for this case we know the distribution for X is given by:
[tex]X \sim N(14,\sqrt{9}=3)[/tex]
Where [tex]\mu=14[/tex] and [tex]\sigma=3[/tex]
We are interested on this probability
[tex]P(X>12)[/tex]
And we can use the z score given by:
[tex]z=\frac{x-\mu}{\sigma}[/tex]
Using this formula we got:
[tex]P(X>12)=P(\frac{X-\mu}{\sigma}>\frac{12-\mu}{\sigma})=P(Z>\frac{12-14}{3})=P(z>-0.67)[/tex]
And we can find this probability with the complement rule and with the normal standard table we got:
[tex]P(z>-0.67)=1-P(z<-0.67)=1-0.2514=0.7486 [/tex]
Answer:
The desired probability is P(X≥12), so subtract from 1 to get P(X≥12)=1−0.2525=0.7475.
Step-by-step explanation:
work out the value of 7^2+4^3 divided by 2^5
113/32
Step-by-step explanation:
7 squared is 49, 4 cubed is 64, 2 to the 5th power is 32.
49 plus 64 is 113 divided by 32
3.53125
Step-by-step explanation:
7^2+4^3/2^5
= 49+64/32
= 113/32
= 3.53125
Daniel, Clarence, and Matthew split a $20.20 dinner bill so that Daniel pays half of what
Clarence pays. If Daniel pays $6.06, what is the ratio of Clarence’s pay to Matthew’s
pay?
Answer:
8.80$
Step-by-step explanation:
Total 20.20. 6.06 x 2=12.12. 20.20-12.12=8.80$
Mathew paid 8.80$
Clarence paid 12.12$
Daniel paid 6.06$
Which statement could be an interpretation of the graph’s x-intercept or y-intercept?
On a coordinate plane, a line goes through points (0, 800) and (400, 0).
Answer:
[tex] m=\frac{y_2 -y_1}{x_2 -x_1} =\frac{0-800}{400-0}= -2[/tex]
And then we can find the y intercept using one point for example (0,800) and we have:
[tex] 800= -2*0+ b[/tex]
[tex] b= 800[/tex]
And our model would be:
[tex] y = -2x +800[/tex]
And the x intercept would be if y=0 then
[tex] 0 =-2x +800[/tex]
[tex] x =400[/tex]
x intercept =400 represent the value of x when y =0
y intercept = 800 represent the value of y when x =0
Step-by-step explanation:
We have the following points given:
(0, 800) and (400, 0)
If we want to find the x intercept and y intercept we need to remember that we need to set a linear model given by:
[tex] y=mx +b[/tex]
Where
[tex] m=\frac{y_2 -y_1}{x_2 -x_1} =\frac{0-800}{400-0}= -2[/tex]
And then we can find the y intercept using one point for example (0,800) and we have:
[tex] 800= -2*0+ b[/tex]
[tex] b= 800[/tex]
And our model would be:
[tex] y = -2x +800[/tex]
And the x intercept would be if y=0 then
[tex] 0 =-2x +800[/tex]
[tex] x =400[/tex]
x intercept =400 represent the value of x when y =0
y intercept = 800 represent the value of y when x =0
Answer:
And then we can find the y intercept using one point for example (0,800) and we have:
And our model would be:
And the x intercept would be if y=0 then
x intercept =400 represent the value of x when y =0
y intercept = 800 represent the value of y when x =0
Step-by-step explanation:
We have the following points given:
(0, 800) and (400, 0)
If we want to find the x intercept and y intercept we need to remember that we need to set a linear model given by:
Where
And then we can find the y intercept using one point for example (0,800) and we have:
And our model would be:
And the x intercept would be if y=0 then
x intercept =400 represent the value of x when y =0
y intercept = 800 represent the value of y when x =0
Step-by-step explanation:
Pythagorean triplet whose one member is 15
Answer:
8,15 and 17 are Pythagorean triplets,the Pythagorean triplets of 15 are: (15,112 and113),(15,8 and 17),(15,20 and 25),(15,9and 12),(15,36 and 39)
Answer:
(8, 15, 17); (9, 12, 15); (15; 20; 25)Step-by-step explanation:
If
[tex]a=m^2-n^2;\ b=2mn;\ c=m^2+n^2[/tex]
for m > n, then a, b, c make a Pythagorean triplet.
[tex]m^2-n^2=15\to(m-n)(m+n)=15\\\\(m-n)(m+n)=(3)(5)\to m-n=3\ \wedge\ m+n=5[/tex]
We have the system of equations:
[tex]\underline{+\left\{\begin{array}{ccc}m-n=3\\m+n=5\end{array}\right}\qquad\text{add both sides of the equations}\\.\qquad2m=8\qquad\text{divide both sides by 2}\\.\qquad\boxed{m=4}[/tex]
Substitute to the second equation:
[tex]4+n=5\qquad\text{subtract 4 from both sides}\\\boxed{n=1[/tex]
Therefore we have:
[tex]a=4^2-1^2=16-1=15\\b=2(4)(1)=8\\c=4^2+1^2=16+1=17[/tex]
[tex]2mn=15[/tex] it's impossible, because 15 is not an even number.
[tex]m^2+n^2=15[/tex]
Let's consider all possible sums of two numbers resulting in 15.
We will check which of the numbers are perfect squares.
1 + 14
2 + 13
3 + 12
4 + 11
5 + 10
6 + 9
7 + 8
(Bold not perfect squares)
There are no two perfect squares among the listed pairs of numbers.
Other:
15, 112, 113
We know the Egyptian triangle with sides of length 3, 4, 5.
By modifying this Pythagorean triplet by multiplying by 3 we get:
(3)(3) = 9; (3)(4) = 12; (3)(5) = 15
By modifying this Pythagorean triplet by multiplying by 5 we get:
(5)(3) = 15; (5)(4) = 20; (5)(5) = 25
Simplify 12 5/8-74/5
Answer:
12x8+5=101/8
101/8-74/5
40/8=5
5x101=505
40/5=8
8x74=592
therefore 505/40-592/40=
-87/40=-2.175
Answer:
The correct answer would be 2.175
Step-by-step explanation:
i got it right :))
What must Bill McGuire invest today to receive an annuity of $12,000 for four years semiannually at a 10% annual rate? All withdrawals will be made at the end of each period.
Answer:
$77,558.55
Step-by-step explanation:
A fix periodic payment for specific period of time.
We need to calculate the present value annuity to determine the value of investment today.
Present value of annuity = P x ( 1 - ( 1 + r )^-n / r )
where
P = Periodic payment = $12,000
r = interest rate = 10% / 2 = 5%
n =numbers of payment = 4 years x 2 = 8 payments
Placing values in the formula
Investment Value today = $12,000 x ( 1 - ( 1 + 5% )^-8 / 5% )
Investment Value today = $77,558.55
A man starts with an initial velocity of 3.50 m/s and accelerates for a distance of 205
m over 28.7 s. What is the acceleration of the man?
Answer:
[tex] X= v_i t + \frac{1}{2}a t^2 [/tex]
And from this equation we can solve for a like this:
[tex] 205m = 3.5m/s *(28.7s) +\frac{1}{2}a (28.7s)^2[/tex]
And solving for a we got:
[tex] 104.55m = \frac{1}{2}a (28.7s)^2[/tex]
[tex] a = \frac{2*104.55m}{(28.7s)^2)}= 0.254 m/s^2[/tex]
Step-by-step explanation:
For this case we have the velocity , distance and time given:
[tex] v = 3.5 m/s, d=205m, t =28.7s[/tex]
And we know from kinematics that he velocity can be expressed like this:
[tex] v_f = v_i +a t[/tex]
We also know that the distance is given by:
[tex] X= v_i t + \frac{1}{2}a t^2 [/tex]
And from this equation we can solve for a like this:
[tex] 205m = 3.5m/s *(28.7s) +\frac{1}{2}a (28.7s)^2[/tex]
And solving for a we got:
[tex] 104.55m = \frac{1}{2}a (28.7s)^2[/tex]
[tex] a = \frac{2*104.55m}{(28.7s)^2)}= 0.254 m/s^2[/tex]
eeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeee
Solution,
Radius=2 m
Area =pi r^2
= 3.142*(2)^2
=12.568 m^2
hope it helps
Good luck on your assignment
A human gene carries a certain disease from the mother to the child with a probability rate of 34%. That is, there is a 34% chance that the child becomes infected with the disease. Suppose a female carrier of the gene has three children. Assume that the infections of the three children are independent of one another. Find the probability that at least one of the children get the disease from their mother.
Answer the following questions:
State the complement of the event "At least one of the children get the disease from their mother".
Find the probability of the complement. Round your answer to four decimals
Find the probability that at least one of the children get the disease from their mother.
Answer:
The probability that at least one of the children get the disease from their mother is 0.7125.
Step-by-step explanation:
We are given that a human gene carries a certain disease from the mother to the child with a probability rate of 34%.
Suppose a female carrier of the gene has three children. Assume that the infections of the three children are independent of one another.
Let Probability that children get the disease from their mother = P(A) = 0.34
SO, Complement of the event "At least one of the children get the disease from their mother"= P(A') = 1 - P(A)
where A' = event that children do not get the disease from mother.
So, P(A') = 1 - P(A) = 1 - 0.34 = 0.66
Now, probability that at least one of the children get the disease from their mother = 1 - Probability that none of the three children get disease from their mother
= 1 - P(X = 0)
= 1 - (0.66 [tex]\times[/tex] 0.66 [tex]\times[/tex] 0.66)
= 1 - 0.2875 = 0.7125
100 thousands equal to ---lakhs
Answer:one lakh....
Step-by-step explanation:I don't say u must have to mark my ans as brainliest but if it has really helped u plz don't forget to thnk me...
Answer:
1 Lakh = 100 Thousands
Step-by-step explanation:
The window above the doorway in Angelica's house is shaped like a semicircle with a diameter of 36 inches.
How much glass was used to make the window? Use 3.14 for π
Answer:
[tex]508.68[/tex] [tex]in^{2}[/tex]
Step-by-step explanation:
[tex]\pi r^{2} (1/2)[/tex]
[tex](3.14)(18^{2})(1/2)[/tex]
[tex]12717/25 = 508.68[/tex]
For the transformation to be a translation, which statements must be true? Select four options.
Answer:
BD = DB'
CG = GC'
m∠EFA = 90°
The line of reflection, EH, is the perpendicular bisector of BB', AA', and CC'.
Step-by-step explanation:
Hope this helps
Correct me if this is wrong
Label the parts of the triangle. Leg leg altitude hypothenuse right angle.
Refer to the provided image.
What is a right-angled triangle?A triangle with one of its angles to be 90°. That is if a triangle has one right angle then the triangle is a right-angled triangle.
What is the hypotenuse of a right-angled triangle?A right-angled triangle's hypotenuse is the longest side. It's the side that's on the opposite side of the right angle.
What is a leg of a right-angled triangle?A leg of a right-angled triangle is the side that is adjacent to the right angle.
What is the altitude of a right-angled triangle?The height of the right-angled triangle when the hypotenuse is considered as the base is called the Altitude of the right-angled triangle.
How to solve it?Considering the definitions above label the figure accordingly.
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On a number line, b, is located the same distance from 0 as another number, a, but in the opposite direction. The number b varies directly with number a. For example b= 11/4 when a= -11/4
A) b=-a
B) -b=-a
C) b-a=0
D) b(-a)=0
Answer:
B and A
Step-by-step explanation:
So based on the facts given, we know that b and a both have the same abasolute value. It does not matter whether a or b is negative or positive.
Please help! Correct answer only, please! The following information matrices show how many of each vehicle type sold and the bonus amount each salesperson receives for selling that type of vehicle for the car dealership for the week. Which salesperson sold the most vehicle for the week described?A. Scott B. Each sold the same number of vehicles C. Kelly D. Mark
Answer: b) Each sold the same number of vehicles
Step-by-step explanation:
This question is only asking for the quantity of vehicles (not the total amount earned) so we can disregard the second matrix and find the sum of each row in the first matrix.
Kelly: 8 + 2 + 6 = 16
Scott: 7 + 8 + 1 = 16
Mark: 10 + 4 + 2 = 16
The total number of vehicles sold by each person is the same
Will pick brainliest! I need help with this, actual effort in answering is much appreciated.
Answer:
option 2
Step-by-step explanation:
4^2=16/8=2. 4^2=16/16=1. 2-1=1
Linek 5
Linem
Line
Linen
-5
Which line has a slope of -3?
A. line j
B. line k
C. line m
D. linen
Assume Shelley Kate decides to take her social security at age 63. What amount of social security benefit will she receive each month, assuming she is entitled to $720 per month
She will receive a lot more money because she is already retired from work already and will win as bit more money
Suppose a box of Cracker Jacks contains one of 5 toy prizes: a small rubber ball, a whistle, a Captain America decoder ring, a race car, or a magnifying glass. Each prize is equally likely to be in a box. Question 1. How many boxes of Cracker Jacks would you expect to buy until you obtain a complete set of prizes
Answer:
11.42 boxes
Step-by-step explanation:
For the first box bought, there is a 100% chance of getting a unique toy (since you still don't have any). E₁ = 1.
After that, there is a 4 in 5 chance of getting a unique toy from the next box, the expected number of boxes required is:
[tex]E_2 = (\frac{4}{5})^{-1} = 1.25[/tex]
For the next unique toy, there is now a 3 in 5 chance of getting it:
[tex]E_3 = (\frac{3}{5})^{-1} = 1.67[/tex]
Following that logic, there is a 2 in 5 chance of getting the 4th unique toy:
[tex]E_4 = (\frac{2}{5})^{-1} = 2.5[/tex]
Finally, there is a 1 in 5 chance to get the last unique toy:
[tex]E_5 = (\frac{1}{5})^{-1} = 5[/tex]
The expected number of boxes to obtain a full set is:
[tex]E=E_1+E_2+E_3+E_4+E_5\\E=1+1.25+1.67+2.5+5\\E=11.42\ boxes[/tex]
find the mean of x,2x,3x,4x,5x
Answer:
Mean = 3x
Step-by-step explanation:
Mean = [tex]\frac{SumOfObservations}{No. OfObservations}[/tex]
Mean = [tex]\frac{x+2x+3x+4x+5x}{5}[/tex]
Mean = [tex]\frac{15x}{5}[/tex]
Mean = 3x
The mean, also known as the average of x, 2x, 3x, 4x, and 5x is 3x as per the concept of Simplifying.
To find the mean of x, 2x, 3x, 4x, and 5x, we need to add up all the values and divide by the total number of values.
In this case, we have five values.
Mean = (x + 2x + 3x + 4x + 5x) / 5
Simplifying the numerator:
Mean = (15x) / 5
Mean = 3x
Therefore, the mean of x, 2x, 3x, 4x, and 5x is 3x.
The mean, also known as the average, represents the central tendency of a set of values. In this case, the mean is 3x, which indicates that on average, the values x, 2x, 3x, 4x, and 5x are three times the value of x.
To learn more about the mean;
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Supplier claims that they are 95% confident that their products will be in the interval of 20.45 to 21.05 you take samples and find that the 95% confidence interval of what they are sending is 20.48 to 21.02 what conclusion can be made
Options:
The supplier products have a lower mean than claimed
The supplier is more accurate than they claimed
The supplier products have a higher mean than claimed
The supplier is less accurate than they have claimed
Answer:
The supplier is less accurate than they have claimed
Step-by-step explanation:
Confidence Interval for supplier claim, CI = (20.45, 21.05)
Confidence Interval for your claim, CI = (20.48, 21.02)
Calculate the mean of the Confidence Interval for the supplier's claim:
[tex]\bar{X_s} = \frac{20.45 + 21.05}{2} \\\bar{X_s} = \frac{41.50}{2}\\\bar{X_s} = 20.75[/tex]
Calculate the mean of the Confidence Interval for your claim :
[tex]\bar{X_y} = \frac{20.48 + 21.02}{2} \\\bar{X_y} = \frac{41.50}{2}\\\bar{X_y} = 20.75[/tex]
Both the supplier and you have the equal mean
Margin of Error by the supplier = 21.05 - 20.75 = 0.30
Margin of Error by you = 21.02 - 20.75 = 0.27
Since the margin of error for the supplier is more, you can conclude that the suppler is less accurate than they have claimed.
The question is incomplete! Complete question along with answer and step by step explanation is provided below.
Question:
Supplier claims that they are 95% confident that their products will be in the interval of 20.45 to 21.05. You take samples and find that the 95% confidence interval of what they are sending is 20.48 to 21.02. What conclusion can be made?
The supplier products have a lower mean than claimed
The supplier is more accurate than they claimed
The supplier products have a higher mean than claimed
The supplier is less accurate than they have claimed
Answer:
The margin of error reported by the supplier is greater as compared to the actual margin of error. A greater margin of error results in less accuracy.
Therefore, we can conclude that the supplier is less accurate than they have claimed.
Step-by-step explanation:
Supplier claims that they are 95% confident that their products will be in the interval of 20.45 to 21.05.
The mean is given by
Mean = (Upper limit + Lower limit)/2
Mean = (21.05 + 20.45)/2
Mean = (41.50)/2
Mean = 20.75
The margin of error in this case is
MoE = Upper limit - Mean
MoE = 21.05 - 20.75
MoE = 0.30
You take samples and find that the 95% confidence interval of what they are sending is 20.48 to 21.02.
The mean is given by
Mean = (Upper limit + Lower limit)/2
Mean = (21.02 + 20.48)/2
Mean = (41.50)/2
Mean = 20.75
The margin of error in this case is
MoE = Upper limit - Mean
MoE = 21.02 - 20.75
MoE = 0.27
As you can notice the margin of error reported by the supplier is greater as compared to the actual margin of error. A greater margin of error results in less accuracy.
Therefore, we can conclude that the supplier is less accurate than they have claimed.
Using the information given, select the statement that can deduce the line segments to be parallel. If there are none select none. When m<7=m<4
Answer:
Option (2). None
Step-by-step explanation:
A quadrilateral ABCD has been given with a property,
m∠7 = m∠4
Option (1). AB║ DC
For AB║DC, angle 7 and angle 3 should measure the same.
(By the property of alternate angles)
Therefore, by the given property we can not deduce AB║DC.
Option (3). AD║BC
For AD║BC, angle 7 and angle 3 must be equal in measure.
(By the property of alternate angles)
Therefore, by the given property we can not deduce AD║DC
Option (2). None will be the answer.
Help me plzzz with my hw
Answer:
w || n and n ⊥ m
Step-by-step explanation:
To find out which statement is true, recall the following:
1. 2 lines are said to be parallel to each other if they do not intersect at any given point and are of the same distant apart. Parallel is denoted by ||
2. 2 lines are said to be perpendicular if both lines intersect at a right angle. It is denoted by ⊥
==>From the diagram given, we can see that w and n are of the same distant apart and they do not intersect at any given point.
Also, we can see that n and m intersect at point X to at right angle.
Therefore, we can conclude that w || n and n ⊥ m
Suppose that T is a one-to-one transformation, so that an equation T(u)=T(v) always implies u=v. Show that if the set of images {T(v1)......T(vp)} is linearly dependent, then {v1......vp} is linearly dependent. This fact shows that a one-to-one linear transformation maps a linearly independent set onto a linearly independent set (because in this case the set of images cannot be linearly dependent).
Answer:
Step-by-step explanation:
The objective is to Show that if the set of images {T(v1)......T(vp)} is linearly dependent, then {v1......vp} is linearly dependent.
Given that:
[tex]\mathbf{[T(v_1) +T(v_2) ...T(v_p)]}[/tex] is linearly dependent set
Thus; there exists scalars [tex]\mathbf{k_1 , k_2 ... k_p}[/tex] ; ( read as "such that") [tex]\mathbf{k_1 T(v_1) +k_2T(v_2) ...k_pT(v_p)=0}[/tex]
[tex]\mathbf{= T(k_1 v_1 +k_2v_2 ...k_pv_p)=0}[/tex]
T = 0 (for the fact that T is linear transformation)
[tex]\mathbf{k_1 v_1 +k_2v_2 ...k_pv_p=0}[/tex] (due to T is one-one)
NOTE: Not all Ki's are zero;
Thus;
[tex]\mathbf{[v_1,v_2 ...v_p] }[/tex] is linearly dependent
It negation also illustrates that :
If [tex]\mathbf{[v_1,v_2 ...v_p]}[/tex] is also linearly independent then [tex]\mathbf{[T(v_1),T(v_2) ...T(v_p)]}[/tex] is also linearly independent.
please help with math, it’s easy!! explantion needed!
Answer:
1
Step-by-step explanation:
The quadratic relation is a perfect square:
y = (7x +3)²
so has one zero, where the factor is zero:
7x +3 = 0
7x = -3
x = -3/7
_____
It is useful to have handy reference to the form of the square of a binomial:
(a +b)² = a² +2ab +b²
Here, your first clue is that 49x² and 9 are both perfect squares: (7x)² and (3)². It is easy to check that the middle term is twice the product of these roots:
2(7x)(3) = 42x . . . . matches the middle term
So, the given expression is equivalent to ...
y = (7x +3)²
Which equation is equivalent to One-fourth + x =Negative StartFraction 5 over 4 EndFraction? Select all that apply.
Options:
(A)x = StartFraction 6 over 4 EndFraction
(B)x = Negative StartFraction 6 over 4 EndFraction
(C)x minus one-fourth = negative StartFraction 5 over 4 EndFraction
(D)x = negative three-halves
(E)x = negative three-fourths
Answer:
(B)x = Negative StartFraction 6 over 4 EndFraction
[tex]-\dfrac{6}{4}[/tex]
(D)x = negative three-halves
[tex]-\dfrac{3}{2}[/tex]
Step-by-step explanation:
We want to determine which fraction is equivalent to
[tex]\dfrac{1}{4}+x=-\dfrac{5}{4}\\$First, we collect like terms$\\x=-\dfrac{5}{4}-\dfrac{1}{4} \\\\=\dfrac{-5-1}{4}\\=-\dfrac{6}{4}\\x=-\dfrac{6}{4}[/tex]
This value of x is the result in Option B.
Reducing [tex]-\dfrac{6}{4}[/tex] to its lowest form:
[tex]-\dfrac{6}{4}=-\dfrac{3}{2}[/tex] which is Option D.
Therefore, the correct options are: B and D
which of the following expressions is equal to 2X^2 +8
Answer:
The question is not clear.
Step-by-step explanation:
Normally it helps to rewrite 8 as
8 = 2 * 2 * 2 = 2³
However the question is not clear.
There are no following expressions given...
By 2X^2 +8,
do you mean 2*x² + 8, or do you mean 2*x^(2 + 8)
or did you perhaps mean 2^(x+8)
Next time, please add a picture.
Answer:
(2x-4i)(x+2i)
Please help me with this math problem
Answer:
see below
Step-by-step explanation:
5x - 6y = 21
Let x = 0 and solve for y to find the y intercept
-6y = 21
Divide by -6
y = 21/-6 = -7/2
The y intercept is (0,-7/2)
5x - 6y = 21
Let y = 0 and solve for x to find the x intercept
5x = 21
Divide by 5
y = 21/5 = 21/5
The x intercept is (21/5,0)
Answer:
x=4.2 (x-intercept)
y=-3.5 (y-intercept)
Step-by-step explanation:
To find the x-intercept, we know that y=0. To find the y-intercept, we know that x=0. All we have to do is plug in 0 into either x or y to find the x-intercept and y-intercept.
X-intercept
5x-6(0)=21
5x-0=21
5x=21
x=4.2
Y-intercept
5(0)-6y=21
0-6y=21
-6y=21
y=-3.5
Results of 99% confidence intervals are consistent with results of two-sided tests with which significance level? Explain the connection. A 99% confidence interval is consistent with a two-sided test with significance level alphaequals nothing because if a two-sided test with this significance level does not reject the null hypothesis, then the confidence interval ▼ contains does not contain the value in the null hypothesis.
Answer:
Yes, they are consistent.
A 99% confidence interval is consistent with a two-sided test with significance level alpha=0.01 because if a two-sided test with this significance level does not reject the null hypothesis, then the confidence interval does contains the value in the null hypothesis.
Step-by-step explanation:
Yes, they are consistent.
A 99% confidence interval is consistent with a two-sided test with significance level alpha=0.01 because if a two-sided test with this significance level does not reject the null hypothesis, then the confidence interval does contains the value in the null hypothesis.
The critical values of the confidence level are equivalent to the critical values in the hypothesis test. In the case that the conclusion of the test is to not reject the null hypothesis, the test statistic falls within the acceptance region: its value is within the critical values of the two-sided test.
Then, it is also within the critical values of the confidence interval and the sample mean (or other measure) will be within the confidence interval bounds.
The rates of on-time flights for commercial jets are continuously tracked by the U.S. Department of Transportation. Recently, Southwest Air had the best rate with 80 % of its flights arriving on time. A test is conducted by randomly selecting 18 Southwest flights and observing whether they arrive on time.
(a) Find the probability that at least 13 flights arrive late .
Answer:
The probability that at least 13 flights arrive late is 2.5196 [tex]\times 10^{-6}[/tex].
Step-by-step explanation:
We are given that Southwest Air had the best rate with 80 % of its flights arriving on time.
A test is conducted by randomly selecting 18 Southwest flights and observing whether they arrive on time.
The above situation can be represented through binomial distribution;
[tex]P(X = x) = \binom{n}{r}\times p^{r} \times (1-p)^{n-r} ; x = 0,1,2,3,.........[/tex]
where, n = number of trials (samples) taken = 18 Southwest flights
r = number of success = at least 13 flights arrive late
p = probability of success which in our question is probability that
flights arrive late, i.e. p = 1 - 0.80 = 20%
Let X = Number of flights that arrive late.
So, X ~ Binom(n = 18, p = 0.20)
Now, the probability that at least 13 flights arrive late is given by = P(X [tex]\geq[/tex] 13)
P(X [tex]\geq[/tex] 13) = P(X = 13) + P(X = 14) + P(X = 15) + P(X = 16) + P(X = 17) + P(X = 18)
= [tex]\binom{18}{13}\times 0.20^{13} \times (1-0.20)^{18-13}+ \binom{18}{14}\times 0.20^{14} \times (1-0.20)^{18-14}+ \binom{18}{15}\times 0.20^{15} \times (1-0.20)^{18-15}+ \binom{18}{16}\times 0.20^{16} \times (1-0.20)^{18-16}+ \binom{18}{17}\times 0.20^{17} \times (1-0.20)^{18-17}+ \binom{18}{18}\times 0.20^{18} \times (1-0.20)^{18-18}[/tex]
= [tex]\binom{18}{13}\times 0.20^{13} \times 0.80^{5}+ \binom{18}{14}\times 0.20^{14} \times 0.80^{4}+ \binom{18}{15}\times 0.20^{15} \times 0.80^{3}+ \binom{18}{16}\times 0.20^{16} \times 0.80^{2}+ \binom{18}{17}\times 0.20^{17} \times 0.80^{1}+ \binom{18}{18}\times 0.20^{18} \times 0.80^{0}[/tex]
= 2.5196 [tex]\times 10^{-6}[/tex].