Answer:
But if we are doing 3^x we need to add both of them
This is a rule you should remember if you have both same base to x power when you are multiplying
5+4 = 9
answer is 3^9 or 19683
Small sample: During an economic downturn, companies were sampled and asked whether they were planning to increase their workforce. Only of the companies were planning to increase their workforce. Use the small-sample method to construct a confidence interval for the proportion of companies that are planning to increase their workforce. Round the answers to at least three decimal places. A confidence interval for the proportion of companies that are planning to increase their workforce is .
Complete Question
The complete question is shown on the first uploaded image
Answer:
The confidence level interval is [tex]0.016 \le C \le 0.404[/tex]
Step-by-step explanation:
The sample size is [tex]n = 20[/tex]
The number planning to increase workforce is [tex]x = 3[/tex]
The confidence level is [tex]c = 98[/tex]%
The value of proportion for a plus 4 method is
[tex]p = \frac{x+2}{n+4}[/tex]
substituting values
[tex]p = \frac{3+2}{20+4}[/tex]
[tex]p =0.21[/tex]
The z-critical value at confidence level of 98% is
[tex]z_{c}=z_{0.98} = 2.33[/tex]
This values is obtained from the standard normal table
The confidence level interval can be mathematically represented as
[tex]C =p \ \pm z_{c} * \sqrt{\frac{p(1-p)}{n+4} }[/tex]
substituting values
[tex]C = 0.21 \pm 2.33 * \sqrt{\frac{0.21(1- 0.21)}{20 +4} }[/tex]
[tex]C = 0.21 \pm 0.194[/tex]
=> [tex]0.016 \le C \le 0.404[/tex]
What’s the correct answer for this question?
Answer:
A and B
Step-by-step explanation:
1) Distance to the focus
From (x,y) to the focus(2,-4) {using distance formula}
=√(x-2)²+(y+4)²
2) Distance to the directrix
Is, y+p where P here is (-6)
So
d2 = y+p
= y+(-6)
= y-6
Ruby has a bird feeder which is visited by an average of 13 birds every 2 hours during daylight hours. What is the probability that the bird feeder will be visited by more than 3 birds in a 40 minute period during daylight hours? Round your answer to three decimal places.
Answer:
62.93%
Step-by-step explanation:
We have to solve it by a Poisson distribution, where:
p (x = n) = e ^ (- l) * l ^ (x) / x!
Where he would come being the number of birds that there would be in 40 minutes, we know that in 2 hours, that is 120 minutes there are 13, therefore in 40 there would be:
l = 13 * 40/120
l = 4,333
Now, we have p (x> 3) and that is equal to:
p (x> 3) = 1 - p (x <= 3)
So, we calculate the probability from 0 to 3:
p (x = 0) = 2.72 ^ (- 4.33) * 4.33 ^ (0) / 0! = 0.01313
p (x = 1) = 2.72 ^ (- 4.33) * 4.33 ^ (1) / 1! = 0.0568
p (x = 2) = 2.72 ^ (- 4.33) * 4.33 ^ (2) / 2! = 0.12310
p (x = 3) = 2.72 ^ (- 4.33) * 4.33 ^ (3) / 3! = 0.17767
If we add each one:
0.01313 + 0.0568 + 0.12310 + 0.17767 = 0.3707
replacing:
p (x> 3) = 1 - 0.3707
p (x> 3) = 0.6293
Which means that the probability is 62.93%
Show that T is a linear transformation by finding a matrix that implements the mapping. Note that x1, x2, ... are not vectors but are entries in vectors. T(X1,X2,X3,X4) = (x1 +4x2, 0, 3x2 +x4, x2 -x4)
The transformation matrix for the mapping T is the matrix T such that
[tex]\mathbf T(\vec x)=T\,\vec x[/tex]
where
[tex]T=\begin{bmatrix}1&4&0&0\\0&0&0&0\\0&3&0&1\\0&1&0&-1\end{bmatrix}[/tex]
The correct matrix A is
[tex]A=\left[\begin{array}{cccc}1&4&0&0\\0&0&0&0\\0&3&0&1&0&1&0&-1\end{array}\right][/tex]
To find the matrix A that represents the linear transformation T, we need to determine the coefficients that map the input vector (X₁, X₂, X₃, X₄) to the output vector (x₁ +4x₂, 0, 3x₂ +x₄, x₂ -x₄)
By comparing the corresponding entries in the input and output vectors, we can determine the coefficients of the matrix A.
The first row of A will have the coefficients for X₁ and X₂, which are 1 and 4 respectively. The second row will have all zeros since the output vector has a zero in the second position. The third row will have the coefficient 3 for X₂ and 1 for X₄. Finally, the fourth row will have the coefficient 1 for X₂ and -1 for X₄.
Thus, the matrix A that implements the mapping T is:
[tex]A=\left[\begin{array}{cccc}1&4&0&0\\0&0&0&0\\0&3&0&1&0&1&0&-1\end{array}\right][/tex]
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A bag contains red and blue marbles, such that the probability of drawing a blue marble is an experiment consists of drawing a
marble, replacing it, and drawing another marble. The two draws are independent. A random variable assigns the number of blue
marbles to each outcome
What is the range of the random variable?
{1,2,3}
{6,7,8)
b. {0,1,2)
d {8, 9, 10
a
С.
Please select the best answer from the choices provided
OOOO
C
Mark this and return
Save and Exit
Next
Submit
Answer:
The range of the random variable is {0, 1, 2}.
Step-by-step explanation:
The bag contains red and blue marbles.
The experiments consists of two draws, with reposition.
The random variable assigns the number of blue marbles to each outcome.
If we have only two draws, we can only get 0, 1 or 2 blue marbles.
The range of the random variable is {0, 1, 2}.
The present value of a perpetuity paying 1 every two years with first payment due immediately is 7.21 at an annual effective rate of i. Another perpetuity paying R every three years with the first payment due at the beginning of year two has the same present value at an annual effective rate of i + 0.01.
Calculate R.
(A) 1.23
(B) 1.56
(C) 1.60
(D) 1.74
(E) 1.94
Answer:
Step-by-step explanation:
image attached (representing first perpetuity on number line)
Present value is 7.21
[tex]7.21=\frac{1}{1-u^2} \\\\1-\frac{1}{7.21} =u^2\\\\\frac{6.21}{7.21} =(1+i)^{-2}\\\\(1+i)^2=\frac{7.21}{6.21} \\\\(i+1)=\sqrt{\frac{7.21}{6.21} }\\\\ i=\sqrt{\frac{7.21}{6.21} } -1\\\\=0.77511297[/tex]
image attached (representing second perpetuity on number line)
we have ,
[tex]7.21=\frac{Ru}{1-u^3}[/tex]
Here,
[tex]V=\frac{1}{1+i}[/tex]i
i = 0.077511297 + 0.01
[tex]\therefore V =\frac{1}{1.087511295} =(1.087511297)^-^1\\\\7.21=\frac{R(1.087511297)^-^1}{1-(1.087511297)^-^3} \\\\7.21=4.132664645R\\\\R=\frac{7.21}{4.132664645} \\\\R= 1.7446370\approx1.74[/tex]
Therefore, value of R is 1.74
What is StartFraction 7 Over 9 EndFraction divided by one-third
Answer:
7/3
Step-by-step explanation:
Write this symbolically as:
7/9
-------
1/3
Invert the denominator fraction and then multiply:
(7/9)(3/1)
Reducing this, we get 7/3
Answer:
the answer as a mixed number is 2 and 1/3 (2 1/3)
and as a normal fraction its 7/3
A survey indicates that shoppers spend an average of 22 minutes with a standard deviation of 8 minutes in your store and that these times are normally distributed. Find the probability that a randomly selected shopper will spend less than 20 minutes in the store.
Answer: 0.401294
Step-by-step explanation:
z=x-μ/σ
z=20-22/8
z=-0.25
the probability for this z-score is 0.401294.
Classify the following triangle. Check all that apply.
35°
10.1
7
102"
6
O A. Isosceles
O B. Equilateral
O c. Obtuse
O D. Right
O E. Scalene
F. Acute
Answer: obtuse and scalene
Step-by-step explanation:
Answer:
Obtuse And Scalene
Step-by-step explanation:
trust me!
Please hurry
On each bounce, a ball dropped from 100 feet rises to the height
from which it has fallen. How high does the ball rise, in feet, on the 10th bounce?
Answer:
D
Step-by-step explanation:
divide 10 times starting with 100.
The answer is 25/256 or 0.09765625
The height of the ball dropped from 100 feet on the 10th bounce is 0.09766 feet
What is an equation?An equation is an expression that shows the relationship between two or more numbers and variables.
Let y represent the height of the ball after x bounce. Given that the ball rises to the height from which it has fallen, hence:
y = 100(1/2)ˣ
After the 10th bounce:
y = 100(1/2)¹⁰ = 0.09766
The height of the ball dropped from 100 feet on the 10th bounce is 0.09766 feet.
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How would you use a completely randomized experiment in each of the following settings?
Is a placebo being used or not? Be specific and give details.
a. A charitable nonprofit organization wants to test two methods of fund-raising. From a list of 1000 past donors, half will be sent literature about the successful activities of the charity and asked to make another donation. The other 500 donors will be contacted by phone and asked to make another donation. The percentage of people from each group who make a new donation will be compared.
b. A tooth-whitening gel is to be tested for effectiveness. A group of 85 adults have volunteered to participate in the study. Of these. 43 are to be given a gel that contains the tooth-whitening chemicals. The remaining 42 are to be given a similar-looking package of gel that does not contain the tooth-whitening chemicals. A standard method will be used to evaluate the whiteness of teeth for all participants. Then the results for the two groups will be compared. How could this experiment he designed to be double-blind?
c. Consider the experiment described in part (a). Describe how you would use a randomized block experiment with blocks based on age. Use three blocks: donors younger than 30 years old. donors 30 to 59 years old. donors 60 and older.
Answer:
Step-by-step explanation:
a. Two methods of fund raising is being tested here in the first case study. To make a completely randomized experiment. I would use and randomly assign half the population of the 1000 donor sample that will be sent literature about the successful activities of the charity and asked to make another donation to one of the two treatment conditions: which is a sent literature about the successful activities of the charity. While the placebo group would be the other 500 donors contacted by phone and asked to make another donation with no influence whatever from the charity.
b. For the second case study, To make a completely randomized experiment. I would use and randomly assign 43 particupants which are to be given a gel that contains the tooth-whitening chemicals to the treatment condition containing the tooth-whitening chemicals while the placebo group would be the remaining 42 which are to be given a similar-looking package of gel that does not contain the tooth-whitening chemicals.
c. Using three blocks: the completely randomized design experiment would be:
Donors younger than 30 years old:
Sent literature: Yes No
Contact by phone: Yes No
Donors 30 to 59 years old:
Sent literature: Yes No
Contact by phone: Yes No
Donors 60 and older:
Sent literature: Yes No
Contact by phone: Yes No
(Yes means yes to another donation and No means no to another donation)
Answer:
Step-by-step explanation:
a. Two methods of fund raising is being tested here in the first case study. To make a completely randomized experiment. I would use and randomly assign half the population of the 1000 donor sample that will be sent literature about the successful activities of the charity and asked to make another donation to one of the two treatment conditions: which is a sent literature about the successful activities of the charity. While the placebo group would be the other 500 donors contacted by phone and asked to make another donation with no influence whatever from the charity.
b. For the second case study, To make a completely randomized experiment. I would use and randomly assign 43 particupants which are to be given a gel that contains the tooth-whitening chemicals to the treatment condition containing the tooth-whitening chemicals while the placebo group would be the remaining 42 which are to be given a similar-looking package of gel that does not contain the tooth-whitening chemicals.
c. Using three blocks: the completely randomized design experiment would be:
Donors younger than 30 years old:
Sent literature: Yes No
Contact by phone: Yes No
Donors 30 to 59 years old:
Sent literature: Yes No
Contact by phone: Yes No
Donors 60 and older:
Sent literature: Yes No
Contact by phone: Yes No
(Yes means yes to another donation and No means no to another donation)
A triangle has sides of lengths 8, 15, and 17. Is it a right triangle? Explain.
Answer:
yes it does
17 is the longest side.
Iff Iff 17%5E2+=+8%5E2+%2B+15%5E2 it's a right triangle. it's a right triangle.
Ps "iff" means if and only if
hope it helps
if so please mark me as brainliest
Given a quadratic function that has solutions at x=4 and x=6 which of the following is one of the linear factors of the function?
A.(x+4)
B.(x-6)
C.(x-2)
D.(x+6)
Answer: THE SOLUTION IS B
x=4 gives the linear factor x-4
x=6 gives the linear factor x-6
Step-by-step explanation:
HELP! Look at the figure, PQRS. Find the values of x and y. a) x = 5, y = 7 b)x = 6, y = 8 c)x = 6, y = 9 d)x = 7, y = 10
Answer:
c) x = 6, y = 9
Step-by-step explanation:
The figure is a parallelogram. The diagonals of a parallelogram bisect each other, so each part of a given diagonal is equal to the other part.
3x = 2y
2x = y+3
__
Solving the second equation for y, we have ...
y = 2x -3
Substituting into the first equation gives ...
3x = 2(2x -3)
3x = 4x -6 . . . . simplify
6 = x . . . . . . . . .add 6 -3x
y = 2(6) -3 = 9 . . . . use the above expression for y
The values of x and y are (x, y) = (6, 9).
The probability of drawing a pearl bead out of a bag of mixed beads is 2/3. What is the probability of drawing a bead which is not a pearl?
Answer:
[tex]\frac{1}{3}[/tex] probability of drawing a bead which is not a pearl
Step-by-step explanation:
For each bead that you draw, there are only two possible outcomes. Either it is a pearl bead, or it is not. The sum of these probabilities = 100% = 1.
So
2/3 probability of drawing a pearl bead.
p probability of drawing a non pearl bead.
What is the probability of drawing a bead which is not a pearl?
[tex]p + \frac{2}{3} = 1[/tex]
[tex]p = 1 - \frac{2}{3}[/tex]
[tex]p = \frac{3*1 - 2}{3}[/tex]
[tex]p = \frac{1}{3}[/tex]
[tex]\frac{1}{3}[/tex] probability of drawing a bead which is not a pearl
the revenue function for a school group selling n bookmarks is given by R(n) =2n and the total cost function is given by C(n)=144+0.08n. determine the number of books
Correction
The revenue function for a school group selling n bookmarks is given by R(n) =2n and the total cost function is given by C(n)=144+0.08n. Determine the number of bookmarks sold at which they break-even.
Answer:
75 bookmarks
Step-by-step explanation:
The break-even point is the point at which revenue earned is equal to the cost of production.
Given the cost and revenue functions respectively:
R(n) =2nC(n)=144+0.08nCost=Revenue
C(n)=R(n)
144+0.08n=2n
144=2n-0.08n
144=1.92n
Divide both sides by 1.92
n=75
When 75 bookmarks are sold, the school group will break even.
A farmer was interest in determining how many grasshoppers were in his field. He knows that the distribution of grasshoppers may not be normally distributed in his field due to growing conditions. As he drives his tractor down each row he counts how many grasshoppers he sees flying away. After several rows he figures the mean number of flights to be 57 with a standard deviation of 12. What is the probability of the farmer will count 52 or fewer flights on average in the next 40 rows down which he drives his tractor
Answer:
= 0.0041
Step-by-step explanation:
Given that:
A farmer was interest in determining how many grasshoppers were in his field. He knows that the distribution of grasshoppers may not be normally distributed in his field due to growing conditions. As he drives his tractor down each row he counts how many grasshoppers he sees flying away
mean number of flights to be 57
a standard deviation of 12
fewer flights on average in the next 40 rows
[tex]\mu = 57\\\\\sigma=12\\\\n=40[/tex]
so,
[tex]P(x<52)[/tex]
[tex]=P(\frac{x-\mu}{\sigma/\sqrt{n} } <\frac{52-57}{12/\sqrt{40} } )\\\\=P(z<\frac{-5\times6.325}{12} )\\\\=P(z<\frac{-31.625}{12})\\\\=P(z<-2.64)[/tex]
using z table
= 0.0041
The probability of the farmer will count 52 or fewer flights on average in the next 40 rows down which he drives his tractor is 0.0041 and this can be determined by using the properties of probability.
Given :
The distribution of grasshoppers may not be normally distributed in his field due to growing conditions.The mean number of flights to be 57 with a standard deviation of 12.The probability of the farmer will count 52 or fewer flights on average in the next 40 rows down which he drives his tractor, can be determined by using the following calculations:
[tex]\rm P(x<52)=P\left (\dfrac{x-\mu}{\dfrac{\sigma}{\sqrt{n} }}<\dfrac{52-57}{\dfrac{12}{\sqrt{40} }}\right)[/tex]
[tex]\rm P(x<52)=P\left (z<\dfrac{-5\times 6.325}{12 }}\right)[/tex]
[tex]\rm P(x<52)=P\left (z<\dfrac{-31.625}{12 }}\right)[/tex]
[tex]\rm P(x<52)=P\left (z<-2.64\right)[/tex]
Now, using z-table:
P(x < 52) = 0.0041
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A tank contains 5,000 L of brine with 13 kg of dissolved salt. Pure water enters the tank at a rate of 50 L/min. The solution is kept thoroughly mixed and drains from the tank at the same rate.
Required:
a. How much salt is in the tank after t minutes?
b. How much salt is in the tank after 20 minutes?
Answer:
a) [tex]x(t) = 13*e^(^-^\frac{t}{100}^)[/tex]
b) 10.643 kg
Step-by-step explanation:
Solution:-
- We will first denote the amount of salt in the solution as x ( t ) at any time t.
- We are given that the Pure water enters the tank ( contains zero salt ).
- The volumetric rate of flow in and out of tank is V(flow) = 50 L / min
- The rate of change of salt in the tank at time ( t ) can be expressed as a ODE considering the ( inflow ) and ( outflow ) of salt from the tank.
- The ODE is mathematically expressed as:
[tex]\frac{dx}{dt} =[/tex] ( salt flow in ) - ( salt flow out )
- Since the fresh water ( with zero salt ) flows in then ( salt flow in ) = 0
- The concentration of salt within the tank changes with time ( t ). The amount of salt in the tank at time ( t ) is denoted by x ( t ).
- The volume of water in the tank remains constant ( steady state conditions ). I.e 10 L volume leaves and 10 L is added at every second; hence, the total volume of solution in tank remains 5,000 L.
- So any time ( t ) the concentration of salt in the 5,000 L is:
[tex]conc = \frac{x(t)}{1000}\frac{kg}{L}[/tex]
- The amount of salt leaving the tank per unit time can be determined from:
salt flow-out = conc * V( flow-out )
salt flow-out = [tex]\frac{x(t)}{5000}\frac{kg}{L}*\frac{50 L}{min}\\[/tex]
salt flow-out = [tex]\frac{x(t)}{100}\frac{kg}{min}[/tex]
- The ODE becomes:
[tex]\frac{dx}{dt} = 0 - \frac{x}{100}[/tex]
- Separate the variables and integrate both sides:
[tex]\int {\frac{1}{x} } \, dx = -\int\limits^t_0 {\frac{1}{100} } \, dt + c\\\\Ln( x ) = -\frac{t}{100} + c\\\\x = C*e^(^-^\frac{t}{100}^)[/tex]
- We were given the initial conditions for the amount of salt in tank at time t = 0 as x ( 0 ) = 13 kg. Use the initial conditions to evaluate the constant of integration:
[tex]13 = C*e^0 = C[/tex]
- The solution to the ODE becomes:
[tex]x(t) = 13*e^(^-^\frac{t}{100}^)[/tex]
- We will use the derived solution of the ODE to determine the amount amount of salt in the tank after t = 20 mins:
[tex]x(20) = 13*e^(^-^\frac{20}{100}^)\\\\x(20) = 13*e^(^-^\frac{1}{5}^)\\\\x(20) = 10.643 kg[/tex]
- The amount of salt left in the tank after t = 20 mins is x = 10.643 kg
Meru Peak is 765 m higher than Mt. Kilimanjaro. If the sum of their heights is 12,555 m, find the height of Mt. Kilimanjaro.
Answer:
Step-by-step explanation:
Let P=Mount Peak
Let K=Mount Killimanjaro
The equation should then be
12555=P+K ...1
P=K+765 ... 2
sub equation 2 into 1
12555=P+P+765
12555=2P+765
12555-765=2P+765-765 (subtracting 765 from both sides)
11790=2P
P=5895, now that we know P
we just make a new equation that was similiar to 1
12555=5895+K
K=6660
the height of Mount K is 6660 Metres
Anyone know the answer ?
Answer:
A. SASD. LLStep-by-step explanation:
Two sides and the angle between are marked as congruent. That immediately tells you that the Side-Angle-Side (SAS) theorem of congruence applies.
The angle is a right angle, which makes the adjacent sides be "legs" of the right triangle. Then the Leg-Leg (LL) theorem of congruence for a right triangle also applies.
Appropriate choices are ...
SAS, LL
Suppose a consumer group suspects that the proportion of households that have three cell phones NOT known to be 30%. A cell phone company has reason to believe that the proportion is 30%. Before they start a big advertising campaign, they conduct a 99% CL hypothesis test. Their marketing people survey 150 households with the result that 43 of the households have three cell phones.
Required:
a. Is the actual percentage of households different from 30%?
b. Set up the hypothesis test.
c. What is the success for this problem?
d. Calculate the p-value.
e. Draw conclusion.
Answer:
We conclude that the actual percentage of households is equal to 30%.
Step-by-step explanation:
We are given that a consumer group suspects that the proportion of households that have three cell phones NOT known to be 30%.
Their marketing people survey 150 households with the result that 43 of the households have three cell phones.
Let p = proportion of households that have three cell phones NOT known.
So, Null Hypothesis, [tex]H_0[/tex] : p = 30% {means that the actual percentage of households is equal to 30%}
Alternate Hypothesis, [tex]H_A[/tex] : p [tex]\neq[/tex] 30% {means that the actual percentage of households different from 30%}
The test statistics that would be used here One-sample z-test for proportions;
T.S. = [tex]\frac{\hat p-p}{\sqrt{\frac{p(1-p)}{n} } }[/tex] ~ N(0,1)
where, [tex]\hat p[/tex] = sample proportion of households having three cell phones = [tex]\frac{43}{150}[/tex] = 0.29
n = sample of households = 150
So, the test statistics = [tex]\frac{0.29-0.30}{\sqrt{\frac{0.30(1-0.30)}{150} } }[/tex]
= -0.27
The value of z test statistic is -0.27.
Also, P-value of the test statistics is given by;
P-value = P(Z < -0.27) = 1 - P(Z [tex]\leq[/tex] 0.27)
= 1 - 0.6064 = 0.3936
Now, at 1% significance level the z table gives critical value of -2.58 and 2.58 for two-tailed test.
Since our test statistic lies within the range of critical values of z, so we have insufficient evidence to reject our null hypothesis as it will not fall in the rejection region due to which we fail to reject our null hypothesis.
Therefore, we conclude that the actual percentage of households is equal to 30%.
A person needs to fill 20 water jugs with a hose. Filling the first 2 jugs has taken 3 minutes. How long to finish filling the remaining jugs
Answer:
Step-by-step explanation:
=20
This take 30 minutes to finish filling the remaining jugs.
What is Multiplication?To multiply means to add a number to itself a particular number of times. Multiplication can be viewed as a process of repeated addition.
Given that;
A person needs to fill 20 water jugs with a hose. Filling the first 2 jugs has taken 3 minutes.
Now,
Let the time to finish filling the remaining jugs = x
Since, A person needs to fill 20 water jugs with a hose. Filling the first 2 jugs has taken 3 minutes.
Hence, By definition of proportion we get;
⇒ 20 / x = 2 / 3
⇒ 20 × 3 / 2 = x
⇒ x = 30
Thus, The time to finish filling the remaining jugs = 30 minutes
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Find the produce 2 1/3 times 3 1/2
Answer:
49/6 or 8 16/99
Step-by-step explanation:
2 1/3 *3 1/2 = (7/3*7/2)= 49/6
First convert to fraction form
then multiply across numerator to numerator and denominator to deominator
Simplify if needed
Turn to mixed fraction if needed
Please answer this correctly
Answer:
452
Step-by-step explanation:
plz mark brainliest!
Answer:
i'll say you have to multiple 9 by 9 than 5 by 5 BUT 23 25 13 and 7 IDK sorry hope i helped :)
Step-by-step explanation:
A multiple-choice standard test contains total of 25 questions, each with four answers. Assume that a student just guesses on each question and all questions are answered independently. (a) What is the probability that the student answers more than 20 questions correctly
Answer:
[tex]P(x>20)=9.67*10^{-10}[/tex]
Step-by-step explanation:
If we call x the number of correct answers, we can said that P(x) follows a Binomial distribution, because we have 25 questions that are identical and independent events with a probability of 1/4 to success and a probability of 3/4 to fail.
So, the probability can be calculated as:
[tex]P(x)=nCx*p^{x}*q^{n-x}=25Cx*0.25^{x}*0.75^{25-x}[/tex]
Where n is 25 questions, p is the probability to success or 0.25 and q is the probability to fail or 0.75.
Additionally, [tex]25Cx=\frac{25!}{x!(25-x)!}[/tex]
So, the probability that the student answers more than 20 questions correctly is equal to:
[tex]P(x>20)=P(21)+P(22)+P(23)+P(24)+P(25)[/tex]
Where, for example, P(21) is equal to:
[tex]P(21)=25C21*0.25^{21}*0.75^{25-21}=9.1*10^{-10}[/tex]
Finally, P(x>20) is equal to:
[tex]P(x>20)=9.67*10^{-10}[/tex]
Classify the triangle by its sides, and then by its angles.
128 degrees
26 degrees
26 degrees
16 cm
16 cm
28 cm
Classified by its sides, the triangle is a(n)
▼
isosceles
scalene
equilateral
triangle.
Classified by its angles, the triangle is a(n)
▼
obtuse
acute
right
triangle.
Consider the homogeneous second-order linear differential equation y′′+4y′−12y=0. Which of the following pairs gives two solutions to this equation? A. y1=e2x,y2=e−6x B. y1=e3x,y2=e1x C. y1=e2x,y2=e−2x D. y1=e−12x,y2=xe−12x E. y1=cos(−12x),y2=sin(−12x) F. y1=e−4x,y2=e−12x Then for these solutions find a particular solution of the form y=c1y1+c2y2 that satisfies the initial conditions y(0)=−5,y′(0)=0. y = y1 + y2.
Given that f(x) = x² + 4x, evaluate f(-2).
Answer:
-4
Step-by-step explanation:
pleas guys can you answer this to me
Answer:
what is this boiii?
Help needed please!!!!!!!!
Olivia recorded the prices of 10 paperback books and 10 hard cover books. Her data is shown.
Paperback: $6.99, $7.49, $12.99, $9.99, $5.99, $8.99, $9.99, $10.00, $3.99, $4.99
Mean: 8.14
Hard cover: $9.99, $12.99, $34.99, $16.99, $15.00, $19.99, $9.99, $10.99, $18.99, $24.99
Mean: 17.49
Which statement is true given the data?
Answer:
C
Step-by-step explanation: