Answer:
Here we have the matrix:
[tex]M = \left[\begin{array}{ccc}1&0\\0&3\end{array}\right][/tex]
And we want to find its inverse.
The inverse of a 2x2 matrix A is:
(1/det(A))*adj(A)
where det(A) is the determinant of the matrix.
Such that for a matrix:
[tex]A = \left[\begin{array}{ccc}a_{11}&a_{12}\\a_{21}&a_{22}\end{array}\right][/tex]
The determinant is:
det(A) = a₁₁*a₂₂ - a₁₂*a₂₁
in the case of our matrix M, the determinant is:
det(M) = 1*3 - 0*0 = 3
and adj(A) is a transposition along the diagonal, and for the other elements, we just change its sign.
Then for our matrix A we would have:
[tex]adj(A) = \left[\begin{array}{ccc}a_{22}&-a_{12}\\-a_{21}&a_{11}\end{array}\right][/tex]
Then for our matrix M, we have:
[tex]adj(M) = \left[\begin{array}{ccc}3&-0\\-0&1\end{array}\right][/tex]
Then the inverse of the matrix M is:
[tex]M^{-1} = \frac{1}{det(M)} *adj(M) = \frac{1}{3}\left[\begin{array}{ccc}3&0\\0&1\end{array}\right] = \left[\begin{array}{ccc}1&0\\0&1/3\end{array}\right][/tex]
O is the center if the regular polygon beloe. Find its perimeter. Round to the nearest tenth if necessary HURRY
Answer:
24.8 units
Step-by-step explanation:
Given
[tex]n = 10[/tex] --- sides
The attached decagon
Required
The perimeter
The decagon is made up of 10 isosceles triangles.
The angle at the vertex of each is:
[tex]Angle = \frac{360}{10}[/tex]
[tex]Angle = 36[/tex]
Next, we create a right-angled triangle from the shape (see attachment)
[tex]\theta[/tex] is calculated as:
[tex]\theta = \frac{Angle}{2}[/tex]
[tex]\theta = \frac{36}{2}[/tex]
[tex]\theta = 18[/tex]
Next, calculate x using:
[tex]\sin(\theta) = \frac{Opposite}{Hypotenuse}[/tex]
So, we have:
[tex]\sin(18) = \frac{x}{4}[/tex]
Make x the subject
[tex]x = 4 * \sin(18)[/tex]
[tex]x = 1.24[/tex]
So, the length (L) of one side of the decagon is:
[tex]L = 2x[/tex]
[tex]L = 2 * 1.24[/tex]
[tex]L = 2.48[/tex]
The perimeter (P) of the shape is:
[tex]P = 10 *L[/tex]
[tex]P = 10 * 2.48[/tex]
[tex]P = 24.8[/tex]
The perimeter of the given polygon rounded to the nearest tenth is; 24.7
What is the perimeter of the Polygon?
The given polygon as we can see has 10 sides.
Now, when we draw a line from the center to the next vertex to the left of the one currently having a line, we will see that the angle can be calculated as; 360/10 = 36° because sum of exterior angles of a polygon sums up to 360°.
Thus, the other two angles will be; (180 - 36)/2 = 72° each
Using sine rule, we can find the length of a side of the polygon as;
x/sin 36 = 4/sin 72
x = (4 * sin 36)/sin 72
x = 2.472
Thus, perimeter = 2.472 * 10 = 24.72 ≈ 24.7
Read more about perimeter at; https://brainly.com/question/397857
IF D and G are the number of degrees and grades of the same angle, prove that G/10=D/9.
Answer:
see explanation
Step-by-step explanation:
The relationship between D and G is
90D = 100G
that is there are 100 grades in 90°
Given any angle in degrees (D)
Divide by 90 to find how many right angles
Then multiply by 100 to convert to grades , so
G = [tex]\frac{D}{90}[/tex] × 100 = [tex]\frac{10}{9}[/tex] D ( multiply both sides by 9 to clear the fraction )
9G = 10D ( divide both sides by 10 )
[tex]\frac{9G}{10}[/tex] = D ( divide both sides by 9 )
[tex]\frac{G}{10}[/tex] = [tex]\frac{D}{9}[/tex]
Greatest to least just need some help will help ty(please don’t give wrong answer)
Answer:
try 91.78, 91.58, 91.26, 363.4
Step-by-step explanation:
In an interview for a secretary position at the dealer, a typist claims a tying speed of 45 words per minute. On
On the basis of 70 trials, she demonstrated an average speed of 43 words per minute with a standard deviation of 15 words per minute.
Test at 5% significance level on the typist’s claim.
Using the hypothesis test for one sample mean, There is NO SIGNIFICANT EVIDENCE to support the typist's claim
[tex]H_{0} = 45\\H_{1} < 45\\\\[/tex]
The test statistic :
T = (x - μ) ÷ (s/√(n))
T = (43 - 45) ÷ (15/√70)
T = - 2 ÷ 1.7928429
T = -1.12
At α = 0.05
Pvalue :
Degree of freedom, df = 70 - 1 = 69
Pvalue = 0.1333
Decision region :
Reject [tex]H_{0}[/tex] if Pvalue < α
0.1333 > 0.05
Since Pvalue > α We fail to reject the Null
Learn more on hypothesis testing: https://brainly.com/question/20262540
please help me with both questions
Answer:
(b) 829 seconds
(c) 13.8 minutes
Step-by-step explanation:
(b) 2.48×10⁸/2.99×10⁵ = 829 seconds
(c) 829/60 = 13.8 minutes
What is the 11th term of this geometric sequence?: 16384, 8192, 4096, 2048
Answer:
16
Step-by-step explanation:
1) Find out r of the sequence. The first term(a1) is 16384, the second term (a2) is 8192.
8192=16384*r. r= 0.5
2) Use the rule that an=a1*r^(n-1)
a11=a1*r^10
a11= 16384*((0.5)^10)= 16384/ (2^10)=16.
if a gallon of milk costs $2.49 how much will 3 1/2 gallons cost
Which of the following would increase the width of a confidence interval for a population mean? Choose the correct answer below. A. Increase the level of confidence B. Decrease the sample standard deviation. C. Increase the sample size D. All of the above
Answer:
A. Increase the level of confidence
Step-by-step explanation:
The margin of error is given by:
The margin of error is:
[tex]M = \frac{Ts}{\sqrt{n}}[/tex]
In which T is related to the level of confidence(the higher the level of confidence, the higher T is), s is the standard deviation of the sample and n is the size of the sample.
Increase the width:
That is, increasing the margin of error, as the width is twice the margin of error, the possible options are:
Increase T -> increase confidence level.
Increase s -> Increase the standard deviation of the sample.
Decrease n -> Decrease the sample size.
Thus, the correct answer is given by option A.
Two coins are tossed. Assume that each event is equally likely to occur. a) Use the counting principle to determine the number of sample points in the sample space. b) Construct a tree diagram and list the sample space. c) Determine the probability that no tails are tossed. d) Determine the probability that exactly one tail is tossed. e) Determine the probability that two tails are tossed. f) Determine the probability that at least one tail is tossed.
Answer:
(a) 4 sample points
(b) See attachment for tree diagram
(c) The probability that no tail is appeared is 1/4
(d) The probability that exactly 1 tail is appeared is 1/2
(e) The probability that 2 tails are appeared is 1/4
(f) The probability that at least 1 tail appeared is 3/4
Step-by-step explanation:
Given
[tex]Coins = 2[/tex]
Solving (a): Counting principle to determine the number of sample points
We have:
[tex]Coin\ 1 = \{H,T\}[/tex]
[tex]Coin\ 2 = \{H,T\}[/tex]
To determine the sample space using counting principle, we simply pick one outcome in each coin. So, the sample space (S) is:
[tex]S = \{HH,HT,TH,TT\}[/tex]
The number of sample points is:
[tex]n(S) = 4[/tex]
Solving (b): The tree diagram
See attachment for tree diagram
From the tree diagram, the sample space is:
[tex]S = \{HH,HT,TH,TT\}[/tex]
Solving (c): Probability that no tail is appeared
This implies that:
[tex]P(T = 0)[/tex]
From the sample points, we have:
[tex]n(T = 0) = 1[/tex] --- i.e. 1 occurrence where no tail is appeared
So, the probability is:
[tex]P(T = 0) = \frac{n(T = 0)}{n(S)}[/tex]
This gives:
[tex]P(T = 0) = \frac{1}{4}[/tex]
Solving (d): Probability that exactly 1 tail is appeared
This implies that:
[tex]P(T = 1)[/tex]
From the sample points, we have:
[tex]n(T = 1) = 2[/tex] --- i.e. 2 occurrences where exactly 1 tail appeared
So, the probability is:
[tex]P(T = 1) = \frac{n(T = 1)}{n(S)}[/tex]
This gives:
[tex]P(T = 1) = \frac{2}{4}[/tex]
[tex]P(T = 1) = \frac{1}{2}[/tex]
Solving (e): Probability that 2 tails appeared
This implies that:
[tex]P(T = 2)[/tex]
From the sample points, we have:
[tex]n(T = 2) = 1[/tex] --- i.e. 1 occurrences where 2 tails appeared
So, the probability is:
[tex]P(T = 2) = \frac{n(T = 2)}{n(S)}[/tex]
This gives:
[tex]P(T = 2) = \frac{1}{4}[/tex]
Solving (f): Probability that at least 1 tail appeared
This implies that:
[tex]P(T \ge 1)[/tex]
In (c), we have:
[tex]P(T = 0) = \frac{1}{4}[/tex]
Using the complement rule, we have:
[tex]P(T \ge 1) + P(T = 0) = 1[/tex]
Rewrite as:
[tex]P(T \ge 1) = 1-P(T = 0)[/tex]
Substitute known value
[tex]P(T \ge 1) = 1-\frac{1}{4}[/tex]
Take LCM
[tex]P(T \ge 1) = \frac{4-1}{4}[/tex]
[tex]P(T \ge 1) = \frac{3}{4}[/tex]
From quadrilateral ABCD is a quadrilateral with area of 48 square units, find the length of AC.
A. 48/5
B. 24
C. 24/5
D. 48
Step-by-step explanation:
I do hope that you understand through the steps in the attachment, if not kindly reach out!
Police estimate that 25% of drivers drive without their seat belts. If they stop 6 drivers at random, find theprobability that more than 4 are wearing their seat belts.
Answer:
%17.80
Step-by-step explanation:
17.8% is the probability that more than 4 are wearing their seat belts.
What is Probability?It is a branch of mathematics that deals with the occurrence of a random event.
Given that Police estimate that 25% of drivers drive without their seat belts.
If they stop 6 drivers at random we need to find the probability that more than 4 are wearing their seat belts.
For each driver stopped, there are only two possible outcomes. Either they are wearing their seatbelts, or they are not.
he drivers are chosen at random, which mean that the probability of a driver wearing their seatbelts is independent from other drivers.
Police estimate that 25% of drivers drive without their seat belts.
This means that 75% wear their seatbelts, so P=0.75
If they stop 6 drivers at random, find the probability that all of them are wearing their seat belts.
[tex]P(X=x)=C_{n,x} p^{x} (1-p)^{n-x}[/tex]
[tex]P(X=6)=C_{6,6} 0.75^{6} (1-0.75)^{0} =0.1780[/tex]
Hence, 17.8% is the probability that more than 4 are wearing their seat belts.
To learn more on probability click:
https://brainly.com/question/11234923
#SPJ5
The math teacher and cheerleading coach have teamed up to help the students do better on their math test. The cheer coach, using dance move names for the positioning of their arms, yells out polynomial functions with different degrees.
For each position the coach yells out, write the shape by describing the position of your left and right arm.
a1. Constant Function:
a2. Positive Linear Function:
a3. Negative Linear Function:
a4. Positive Quadratic Function:
a5. Negative Quadratic Function:
a6. Positive Cubic Function:
a7. Negative Cubic Function:
a8. Positive Quartic Function:
a9. Negative Quartic Function:
When it comes time to take the test not only do the students have to describe the shape of the polynomial function, you have to find the number of positive and negative real zeros, including complex. Use the equation below:
[tex]f(x)=x^5-3x^4-5x^3+5x^2-6x+8[/tex]
b. Identify all possible rational zeros.
c. How many possible positive real zeros are there? How many possible negative real zeros? How many possible complex zeros?
d. Graph the polynomial to approximate the zeros. What are the rational zeros? Use synthetic division to verify these are correct.
e. Write the polynomial in factor form.
f. What are the complex zeros?
Step-by-step explanation:
a1. The shape will be a vertical or horizontal line.
a2. The shape will be shaped like a diagonal line increasing as we go right.
a3. The shape will be shaped like a diagonal line decreasing as we go right.
a4. The shape will be shaped like a U facing upwards.
a5.The shape will be shaped like a U facing downwards.
a6. The shape will look like a S shape and it increases as we go right.
a7. The shape will look like a S shape and it decreases as We go right.
a8. The shape look like a W shape and it facing upwards.
a9. The shape look a W shape facing downwards.
We are given function.
[tex]x {}^{5} - 3x {}^{4} - 5x {}^{3} + 5x {}^{2} - 6x + 8[/tex]
b. We can test by the Rational Roots Test,
This means a the possible roots are
plus or minus(1,2,4,8).
c. If we apply Descrates Rule of Signs,
There are 3 possible positive roots or 1 possible positive root.There are also 1 possible negative root.There is also 1 possible complex root.d. Use Desmos to Graph the Function. Some roots are (-2,1,4).
e.
[tex](x {}^{2} + 1) (x - 1)(x - 4)(x + 2)[/tex]
f. The complex zeroes are
i and -i
Polynomial [tex]f(x) = x^{5} -3x^{4} - 5x^{3} + 5x^{2} - 6x + 8[/tex] in factor form: (x-1)(x+2)(x-4)(x-i)(x+i)
What is a polynomial?A polynomial is an expression consisting of indeterminates and coefficients, that involves only the operations of addition, subtraction, multiplication, and non-negative integer exponentiation of variables.
Shape of the graph for the following polynomial:
Constant function - straight line parallel to x axis.Positive linear function - straight line slanting upwards from left to right.Negative linear function - straight line slanting downwards from left to right.Positive quadratic function - U shaped curve opening upwardsNegative quadratic function - U shaped curve opening downwardsPositive cubic function - right hand curved upwards, left hand curved downwards.Negative cubic function - Left hand curved upwards, right hand curved downwards. Positive quartic function - W shaped facing upwardsNegative quartic function - W shaped facing downwardsFinding zeros of the polynomial given:
[tex]f(x) = x^{5} -3x^{4} - 5x^{3} + 5x^{2} - 6x + 8[/tex]
By factor theorem, if f(t) = 0, t is a zero of the polynomial.
Taking t = 1.
f(1) = 1 - 3 - 5 + 5 - 6 + 8 = 0
(x - 1) is a factor of the polynomial f(x).
Divide f(x) by (x-1) using long division to find the other factors.
f(x)/(x-1) = [tex]x^{4} -2x^{3}-7x^{2} -2x-8[/tex] is also a factor of f(x).
Factorizing it further:
g(x) = [tex]x^{4} -2x^{3}-7x^{2} -2x-8[/tex]
g(-2) = 16 + 16 - 28 + 4 - 8 = 0
(x + 2) is a factor of g(x) and thus f(x).
g(x)/(x+2) = [tex]x^{3} - 4x^{2} +x - 4[/tex] is a factor of f(x).
Factorizing it further:
k(x) = [tex]x^{3} - 4x^{2} +x - 4[/tex]
k(4) = 64 - 64 + 4 - 4 = 0
(x - 4) is a factor of k(x) thus of f(x).
k(x)/(x-4) = [tex]x^{2} +1[/tex]
Factorizing it further:
l(x) = [tex]x^{2} +1[/tex] = (x + i)(x - i)
Zeros of f(x) = 1, -2, 4, ±i
Rational zeros : 1, -2, 4
Positive real zeros: 1, 4
Negative real zeros: -2
Complex zeros: ±i
Polynomial in factor form: (x-1)(x+2)(x-4)(x-i)(x+i).
Learn more about polynomial here
https://brainly.com/question/11536910
#SPJ2
Find the distance of the point (4,4,−4) from the line r(t)=⟨−1+2t,1+2t,3−3t⟩.
Translate the given point and line together so that you get a new point and a new line that passes through the origin. This turns the problem into finding the distance between the new point,
p = (4, 4, -4) - (-1, 1, 3) = (5, 3, -7)
and the new line,
r*(t) = r(t) - ⟨-1, 1, 3⟩ = ⟨2t, 2t, -3t⟩
Let p = ⟨5, 3, -7⟩, the vector starting at the origin and pointing to p. Then the quantity ||p - r*(t)|| is the distance from the point p to the line r*(t).
Let u be such that ||p - r*(t)|| is minimized. At the value t = u, the vector p - r*(t) is orthogonal to the line r*(t), so that
(p - r*(u) ) • r*(u) = 0
I've attached a sketch with all these elements in case this description is confusing. (The red dashed line is meant to be perpendicular to r*(t).)
Solve this equation for u :
p • r*(u) - r*(u) • r*(u) = 0
p • r*(u) = r*(u) • r*(u)
and x • x = ||x||² for any vector x, so
p • r*(u) = ||r*(u)||²
⟨5, 3, -7⟩ • ⟨2u, 2u, -3u⟩ = (2u)² + (2u)² + (-3u)²
10u + 6u + 21u = 4u ² + 4u ² + 9u ²
17u ² - 37u = 0
u (17u - 37) = 0
==> u = 0 or u = 37/17
We ignore u = 0, since the dot product of any vector with the zero vector is 0.
Then the minimum distance distance between the given point and line is
||p - r*(u)|| = ||⟨5, 3, -7⟩ - 37/17 ⟨2, 2, -3⟩|| = √(42/17)
Suppose 1 in 5 (1/5) JWU students own their own car. If four students are randomly selected, what is the probability that all four own their car?
Answer:
1/625 = 0.0016
Step-by-step explanation:
update, oh sorry, this is about 4 picks and not 5.
so, it is 1/5⁴ = 1/625 = 0.0016
1 in 5 own their own car.
that is 20% or a chance of 1/5 = 0.2 of picking a student owning a car.
let's assume that the total number of students is large enough that each pick does not change the individual probabilities.
each event (picking a student and checking the ownership of a car) is independent and non-overlapping.
so, the probability that all 5 own a car is the chance of picking the 5th student owning a car AND all 4 previous student picks owning a car.
the probability that all 4 previous picks own a car is the chance of picking the fourth student owning a car AND all 3 previous student picks owning a car.
the probability that all 3 previous picks own a car is the chance of picking the third student owning a car AND all 2 previous student picks owning a car.
the probability that all 2 previous picks own a car is the chance of picking the second student owning a car AND the previous student pick owning a car.
the probability that the first student pick owns a car is 1/5 or 0.2
so, we have a clean
1/5×1/5×1/5×1/5×1/5 = 1/5⁵ probability = 1/3125 = 0.00032
F(x)=-2x^2+4x+5
Find the critical numbers
Answer:
To find critical points, take the first derivative and set it equal to zero:
f(x) = -2x^2 + 4x + 5
f'(x) = -4x + 4
-4x+4 = 0
-4x = -4
x = 1
Critical point at x = 1
Alternatively, if you mean zeros, or where the x intersects, you can use the quadratic equation.
HELP PLEASE!!!
Oak wilt is a fungal disease that infects oak trees. Scientists have discovered that a single tree in a small forest is infected with oak wilt. They determined that they can use this exponential model to predict the number of trees that will be infected after t years.
f(t)=e^0.4t
Question:
Rewrite the exponential model as a logarithmic model that calculates the # of years, g(x) for the number of infected trees to reach a value of x.
The logarithmic model is:
[tex]g(x) = \frac{\ln{x}}{0.4}[/tex]
-------------
We are given an exponential function, for the amount of infected trees f(x) after x years.To find the amount years needed for the number of infected trees to reach x, we find the inverse function, applying the natural logarithm.-------------
The original function is:
[tex]y = f(x) = e^{0.4x}[/tex]
To find the inverse function, first, we exchange y and x, so:
[tex]e^{0.4y} = x[/tex]
Now, we have to isolate y, and we start applying the natural logarithm to both sides of the equality. So
[tex]\ln{e^{0.4y}} = \ln{x}[/tex]
[tex]0.4y = \ln{x}[/tex]
[tex]y = \frac{\ln{x}}{0.4}[/tex]
Thus, the logarithmic model is:
[tex]g(x) = \frac{\ln{x}}{0.4}[/tex]
A similar question is given at https://brainly.com/question/24290183
Determine if the described set is a subspace. Assume a, b, and c are real numbers. The subset of R3 consisting of vectors of the form [a b c] , where at most one of a , b and c is non 0.
The set is a subspace.
The set is not a subspace.
If so, give a proof. If not, explain why not.
Answer:
Not a subspace
Step-by-step explanation:
(4,0,0) and (0,4,0) are vectors in R3 with zero or one entries being nonzero, but their sum, (4,4,0) has two nonzero entries.
Solve this problem:
5X +8 = 53
5X + 8 = 53
5X = 53 - 8
X = 45 / 5
X = 9
Answer:
X=9
Step-by-step explanation:
5X+8=53
To solve this we need to make X the subject of the equation that means X should be alone on one side of the equation. Taking the following steps
5X=53-8
5X=45
X=45/5
X=9
Question
Find the volume of a cone with a height of 9 centimeters and a radius of 5 centimeters.
Use 3.14 to approximate pi, round your answer to the nearest hundredth if necessary, and do not include units.
Answer:
235.5
Step-by-step explanation:
Substitute the values into the equation [tex]V=\pi r^2 \frac{h}{3}[/tex], which is the formula for finding the volume of a cone.
[tex]V=(3.14)(5^2)\frac{(9)}{3}[/tex]
Simplify.
[tex]V=(3.14)(25)(3)[/tex]
Simplify again.
[tex]V=(78.5)(3)[/tex]
Simplify for the last time.
[tex]V=235.5[/tex]
Note, using 3.14 will give you 235.5, but if you use the [tex]\pi[/tex] button on a scientific calculator, your answer will be 235.62. Given the constraints of the problem, your best bet will be 235.5.
[tex]Solve. Clear fraction first.6/5 + 2/5 x = 89/30 + 7/6 x + 1/6[/tex]
Step-by-step explanation:
we have denominators 5, 6 and 30.
the smallest number that is divisible by all 3 is clearly 30.
so, we have to multiply everything by 30 to eliminate the fractions.
180/5 + 60/5 x = 89 + 210/6 x + 30/6 =
36 + 12x = 89 + 35x + 5
-58 = 23x
x = -58/23
Please help I don’t know the answer
The last option is none of the above
Answer:
The two lines are:
y=x+2 and y=-2x+6
Dotted lines represent < or >, whereas the opposite is true for solid lines.
So the correct answer is the first option.
Hope this helps!
y = (4x+4)^1/2 at x=2
9514 1404 393
Answer:
2√3 ≈ 3.4641016
Step-by-step explanation:
Put the value where the variable is and do the arithmetic.
(4x +4)^(1/2) at x=2 is ...
(4·2 +4)^(1/2) = 12^(1/2) = 2√3 ≈ 3.4641016
__
Additional comment
If you really mean (4x+4)^1/2, then you have 12^1/2 = 12/2 = 6.
If the exponent is 1/2, it needs to be in parentheses.
There are 165 children taking swimming lessons at the pool. If 10 children will be assigned to each instructor, how many instructors are needed?
Answer:
17 instructors
Step-by-step explanation:
If each instructor will get 10 children, we have to divided the total number of children taking swimming lessons by the number of children assigned to each instructor (10):
165/10 = 16.5
Unfortunately, we can't have 16 and a half instructors. Since 5 children are remaining, we can round up 16.5 to 17 and get 17 instructors. This implies that 16 instructors will teach 10 children (160 in total) and 1 instructor will teach 5 children (5 in total). 160+5 = 165 total children.
What is the value of p?
A. 125°
B. 45°
C. 35°
D. 550
Answer:
C- 35 °
Step-by-step explanation:
Interior angle adjacent to 90° angle = 90° (supplementary angles of a line segment).
Interior angle adjacent to 125° angle = 55° (supplementary angles of a line segment).
Sum of two interior angles of the triangle = 55+90 = 145°
∠p = 180° - 145° = 35°
A sample of 42 observations is selected from one population with a population standard deviation of 3.3. The sample mean is 101.0. A sample of 53 observations is selected from a second population with a population standard deviation of 3.6. The sample mean is 99.0. Conduct the following test of hypothesis using the 0.04 significance level.
H0 : μ1 = μ2
H1 : μ1 ≠ μ2
a. State the decision rule.
b. Compute the value of the test statistic.
c. What is your decision regarding H0?
d. What is the p-value?
Answer:
a)
[tex]|z| < 2.054[/tex]: Do not reject the null hypothesis.
[tex]|z| > 2.054[/tex]: Reject the null hypothesis.
b) [tex]z = 2.81[/tex]
c) Reject.
d) The p-value is 0.005.
Step-by-step explanation:
Before testing the hypothesis, we need to understand the central limit theorem and the subtraction of normal variables.
Central Limit Theorem
The Central Limit Theorem establishes that, for a normally distributed random variable X, with mean [tex]\mu[/tex] and standard deviation [tex]\sigma[/tex], the sampling distribution of the sample means with size n can be approximated to a normal distribution with mean [tex]\mu[/tex] and standard deviation [tex]s = \frac{\sigma}{\sqrt{n}}[/tex].
For a skewed variable, the Central Limit Theorem can also be applied, as long as n is at least 30.
Subtraction between normal variables:
When two normal variables are subtracted, the mean is the difference of the means, while the standard deviation is the square root of the sum of the variances.
Population 1:
Sample of 42, standard deviation of 3.3, mean of 101, so:
[tex]\mu_1 = 101[/tex]
[tex]s_1 = \frac{3.3}{\sqrt{42}} = 0.51[/tex]
Population 2:
Sample of 53, standard deviation of 3.6, mean of 99, so:
[tex]\mu_2 = 99[/tex]
[tex]s_2 = \frac{3.6}{\sqrt{53}} = 0.495[/tex]
H0 : μ1 = μ2
Can also be written as:
[tex]H_0: \mu_1 - \mu_2 = 0[/tex]
H1 : μ1 ≠ μ2
Can also be written as:
[tex]H_1: \mu_1 - \mu_2 \neq 0[/tex]
The test statistic is:
[tex]z = \frac{X - \mu}{s}[/tex]
In which X is the sample mean, [tex]\mu[/tex] is the value tested at the null hypothesis, and s is the standard error .
a. State the decision rule.
0.04 significance level.
Two-tailed test(test if the means are different), so between the 0 + (4/2) = 2nd and the 100 - (4/2) = 98th percentile of the z-distribution, and looking at the z-table, we get that:
[tex]|z| < 2.054[/tex]: Do not reject the null hypothesis.
[tex]|z| > 2.054[/tex]: Reject the null hypothesis.
b. Compute the value of the test statistic.
0 is tested at the null hypothesis:
This means that [tex]\mu = 0[/tex]
From the samples:
[tex]X = \mu_1 - \mu_2 = 101 - 99 = 2[/tex]
[tex]s = \sqrt{s_1^2 + s_2^2} = \sqrt{0.51^2 + 0.495^2} = 0.71[/tex]
Value of the test statistic:
[tex]z = \frac{X - \mu}{s}[/tex]
[tex]z = \frac{2 - 0}{0.71}[/tex]
[tex]z = 2.81[/tex]
c. What is your decision regarding H0?
[tex]|z| = 2.81 > 2.054[/tex], which means that the decision is to reject the null hypothesis.
d. What is the p-value?
Probability that the means differ by at least 2, either plus or minus, which is P(|z| > 2.81), which is 2 multiplied by the p-value of z = -2.81.
Looking at the z-table, z = -2.81 has a p-value of 0.0025.
2*0.0025 = 0.005
The p-value is 0.005.
which table shows a proportional relationship between x and y?
Answer:
Table C
Step-by-step explanation:
For x and y to be proportional , then the values of
[tex]\frac{y}{x}[/tex] = constant k
Table B
[tex]\frac{y}{x}[/tex] = [tex]\frac{6}{3}[/tex] = 2
[tex]\frac{y}{x}[/tex] = [tex]\frac{24}{6}[/tex] = 4
[tex]\frac{y}{x}[/tex] = [tex]\frac{36}{9}[/tex] = 4
The values are not constant
Table C
[tex]\frac{y}{x}[/tex] = [tex]\frac{2}{3}[/tex]
[tex]\frac{y}{x}[/tex] = [tex]\frac{4}{6}[/tex] = [tex]\frac{2}{3}[/tex]
[tex]\frac{y}{x}[/tex] = [tex]\frac{6}{9}[/tex] = [tex]\frac{2}{3}[/tex]
These values are constant
Then Table C shows a proportional relationship between x and y
kabura bought a piece of cloth 3 metres long. The material shrunk by 1% after washing. What was the new length of the cloth
Answer:
2.97m
Step-by-step explanation:
1% of 3m =1/100×3=0.03
0.03m of cloth was shrunk,
So, New lenght : 3-0.03=2.97m
Please help me! I need answer asap
Answer:
1/10
Step-by-step explanation:
1/5*1/2
1/10
Round 5,821 to the nearest thousands place:
Answer:
6000 hope this helps
if the question is 5,422 then the round figure is 5000
but the question is 5,821 its above 5500 will be 6000
Find the slope of the line passing through the points (-1, 7) and (-5, 1)
Answer:
3/2
Step-by-step explanation:
y2 - y1 / x2 - x1
1 - 7 / -5 - (-1)
-6 / -4
= 3/2
Answer:
m=3/2
Step-by-step explanation:
m=y2-y1/x2-x1
m=1-7/-5-(-1)
m=-6/-4
m=3/2