Answer:
(a) The value of E (X) is 4/7.
The value of V (X) is 3/98.
(b) The value of P (X ≤ 0.5) is 0.3438.
Step-by-step explanation:
The random variable X is defined as the proportion of surface area in a randomly selected quadrant that is covered by a certain plant.
The random variable X follows a standard beta distribution with parameters α = 4 and β = 3.
The probability density function of X is as follows:
[tex]f(x) = \frac{x^{\alpha-1}(1-x)^{\beta-1}}{B(\alpha,\beta)} ; \hspace{.3in}0 \le x \le 1;\ \alpha, \beta > 0[/tex]
Here, B (α, β) is:
[tex]B(\alpha,\beta)=\frac{(\alpha-1)!\cdot\ (\beta-1)!}{((\alpha+\beta)-1)!}[/tex]
[tex]=\frac{(4-1)!\cdot\ (3-1)!}{((4+3)-1)!}\\\\=\frac{6\times 2}{720}\\\\=\frac{1}{60}[/tex]
So, the pdf of X is:
[tex]f(x) = \frac{x^{4-1}(1-x)^{3-1}}{1/60}=60\cdot\ [x^{3}(1-x)^{2}];\ 0\leq x\leq 1[/tex]
(a)
Compute the value of E (X) as follows:
[tex]E (X)=\frac{\alpha }{\alpha +\beta }[/tex]
[tex]=\frac{4}{4+3}\\\\=\frac{4}{7}[/tex]
The value of E (X) is 4/7.
Compute the value of V (X) as follows:
[tex]V (X)=\frac{\alpha\ \cdot\ \beta}{(\alpha+\beta)^{2}\ \cdot\ (\alpha+\beta+1)}[/tex]
[tex]=\frac{4\cdot\ 3}{(4+3)^{2}\cdot\ (4+3+1)}\\\\=\frac{12}{49\times 8}\\\\=\frac{3}{98}[/tex]
The value of V (X) is 3/98.
(b)
Compute the value of P (X ≤ 0.5) as follows:
[tex]P(X\leq 0.50) = \int\limits^{0.50}_{0}{60\cdot\ [x^{3}(1-x)^{2}]} \, dx[/tex]
[tex]=60\int\limits^{0.50}_{0}{[x^{3}(1+x^{2}-2x)]} \, dx \\\\=60\int\limits^{0.50}_{0}{[x^{3}+x^{5}-2x^{4}]} \, dx \\\\=60\times [\dfrac{x^4}{4}+\dfrac{x^6}{6}-\dfrac{2x^5}{5}]\limits^{0.50}_{0}\\\\=60\times [\dfrac{x^4\left(10x^2-24x+15\right)}{60}]\limits^{0.50}_{0}\\\\=[x^4\left(10x^2-24x+15\right)]\limits^{0.50}_{0}\\\\=0.34375\\\\\approx 0.3438[/tex]
Thus, the value of P (X ≤ 0.5) is 0.3438.
What is the general form of the equation of the line shown? 2 x - y + 3 = 0 2 x - y - 3 = 0 x - 2 y - 3 = 0
Answer:
2x - y - 3 = 0
Step-by-step explanation:
Find slope-intercept form first: y = mx + b
Step 1: Pick out 2 points
In this case, I picked out (2, 1) and (0, -3) from the graph
Step 2: Using slope formula y2 - y1/x2 - x1 to find slope
-3 - 1/0 - 2
m = 2
Step 3: Place slope formula results into point-slope form
y = 2x + b
Step 4: Plug in a point to find b
-3 = 2(0) + b
b = -3
Step 5: Write slope-intercept form
y = 2x - 3
Step 6: Move all variables and constants to one side
0 = 2x - 3 - y
Step 7: Rearrange
2x - y - 3 = 0 is your answer
If the terms of a polynomial do not have a GCF, does that mean it is not factorable?
A woman has a collection of video games and anime. she has 50 anime DVDs, and she has 70 video games. which it adds up to 120 items. if you divide them by 5, how many items does she have all together?
Answer:
24
Step-by-step explanation:
Since you are given almost everything, you just simply divide by 5=>
120/5 = 24
Hope this helps
What transformations to the linear parent function, f(x) = x, give the function
g(x) = 4x - 2? Select all that apply.
A. Shift down 2 units.
B. Vertically stretch by a factor of 4.
O c. Horizontally stretch by a factor of 4.
O D. Shift left 2 units.
Answer:
A. Shift down 2 units.
B. Vertically stretch by a factor of 4.
Step-by-step explanation:
Given the function
f(x)=x
If we stretch y vertically by a factor of m, we have: y=m·f (x)
Therefore:
Vertically stretching f(x) by a factor of 4, we have: 4x.
Next, if we take down f(x) by k units we have: y= f(x)-k
Therefore: Taking down 4x by 2 units, we obtain:
g(x)=4x-2
Therefore, Options A and B applies.
Can someone please explain how to do this problem? The websites instructions are very poor. Rewrite [tex]\frac{2}{x^{2} -x-12}[/tex] and [tex]\frac{1}{x^{2}-16 }[/tex] as equivalent rational expressions with the lowest common denominator.
Answer: x = -5
Step-by-step explanation:
If you factor each denominator, you can find the LCM.
[tex]\dfrac{2}{x^2-x-12}=\dfrac{1}{x^2-16}\\\\\\\dfrac{2}{(x-4)(x+3)}=\dfrac{1}{(x-4)(x+4)}\\\\\\\text{The LCM is (x-4)(x+4)(x+3)}\\\\\\\dfrac{2}{(x-4)(x+3)}\bigg(\dfrac{x+4}{x+4}\bigg)=\dfrac{1}{(x-4)(x+4)}\bigg(\dfrac{x+3}{x+3}\bigg)\\\\\\\dfrac{2(x+4)}{(x-4)(x+4)(x+3)}=\dfrac{1(x+3)}{(x-4)(x+4)(x+3)}\\[/tex]
Now that the denominators are equal, we can clear the denominator and set the numerators equal to each other.
2(x + 4) = 1(x + 3)
2x + 8 = x + 3
x + 8 = 3
x = -5
Help solve attached question.
Answer:
[tex]\mathrm{12\sqrt{5} \: \: inches}[/tex]
Step-by-step explanation:
Use Pythagorean theorem, where:
[tex]a^2+b^2=c^2[/tex]
Substitute in the values.
[tex]24^2+12^2=c^2[/tex]
[tex]c^2=576+144[/tex]
[tex]c^2=720[/tex]
[tex]c=\sqrt{720}[/tex]
[tex]c=12\sqrt{5}[/tex]
[tex]c=26.83281[/tex]
If
f(x) = 13x + 1, then
f-1(x) =
Answer:
(x-1)/13
Step-by-step explanation:
y = 13x+1
To find the inverse, exchange x and y
x = 13y+1
Solve for y
Subtract 1 from each side
x-1 =13y+1-1
x-1 = 13y
Divide each side by 13
(x-1)/13 = y
The inverse is (x-1)/13
Answer:
f(x) = 13x + 1
To find the inverse let f(x) = y
y = 13x + 1
x = 13y + 1
13y = x - 1
y = (x-1)/13
The inverse is x-1/13.
given the diagram below what is cos (45degree)?
Answer:
[tex]1/\sqrt{2}[/tex]
Answer:
B
Step-by-step explanation:
Assume that the population proportion is 0.56. Compute the standard error of the proportion, σp, for sample sizes of 100, 200, 500, and 1,000. (Round your answers to four decimal places.)
Answer:
Standard errors are 0.049, 0.035, 0.022, and 0.016.
Step-by-step explanation:
The given value of population proportion (P) = 0.56
Given sample sizes (n ) 100, 200, 500, and 1000.
Now standard error is required to calculate.
Use the below formula to find standard error.
When sample size is n = 100
[tex]\sqrt{\frac{P(1-P)}{n}} = \sqrt{\frac{0.56(1-0.56)}{100}} =0.049[/tex]
When sample size is n = 200
[tex]\sqrt{\frac{P(1-P)}{n}} = \sqrt{\frac{0.56(1-0.56)}{200}} = 0.035[/tex]
When sample size is n = 500
[tex]\sqrt{\frac{P(1-P)}{n}} = \sqrt{\frac{0.56(1-0.56)}{500}} =0.022[/tex]
When sample size is n = 1000
[tex]\sqrt{\frac{P(1-P)}{n}} = \sqrt{\frac{0.56(1-0.56)}{1000}} = 0.016[/tex]
A polynomial is factorable, but it is not a perfect square trinomial or a
difference of two squares. Can you factor the polynomial without finding the GCF?
Answer:
So in this problem, we're told that a polynomial is fact herbal and it's not a perfect square. Try no meal or a difference of two squares. Can you factor the pie? Nomi bite or polynomial without finding the G C F. So no Jacey after is allowed. So if it's not a perfect squared, try no meal. So not a perfect square. We know it's not this, and we also know it's not a difference of two squirt if it's not any of these or if it's not either of these, but we can't find the G. C F. There are three different ways we could find the factored form. You could do it by grouping where you separating the polynomial into two parts and factor them individually before combining. You could also use the sum or a difference of cubes. This is for a cubic or a um, polynomial of third degree, and you could also use fractional or negative exponents. So even if you can't find the G c f or use these methods, there are still three ways you can factor the
Step-by-step explanation:
Glad i could help!
If the radius of a circle is 31.2 cm, what is the approximate area if you use 3.14 for pi and the area is rounded to the nearest tenth?
Answer:
3056.6 cm^2
Step-by-step explanation:
A = (pi)r^2 = 3.14 * 31.2 cm * 31.2 cm = 3056.6 cm^2
Answer: 3056.60 sq. cm.
Step-by-step explanation:
Area of a circle = π x r^2
= 3.14 x 31.2^2
= 3056.60
In a sample of 22 people, the average cost of a cup of coffee is $2.70. Assume the population standard deviation is $0.93. What is the 90% confidence interval for the cost of a cup of coffee
Answer:
$2.70+/-$0.33
= ( $2.37, $3.03)
Therefore, the 90% confidence interval (a,b) = ( $2.37, $3.03)
Step-by-step explanation:
Confidence interval can be defined as a range of values so defined that there is a specified probability that the value of a parameter lies within it.
The confidence interval of a statistical data can be written as.
x+/-zr/√n
Given that;
Mean x = $2.70
Standard deviation r = $0.93
Number of samples n = 22
Confidence interval = 90%
z(at 90% confidence) = 1.645
Substituting the values we have;
$2.70+/-1.645($0.93/√22)
$2.70+/-1.645($0.198276666210)
$2.70+/-$0.326165115916
$2.70+/-$0.33
= ( $2.37, $3.03)
Therefore, the 90% confidence interval (a,b) = ( $2.37, $3.03)
The state education commission wants to estimate the fraction of tenth grade students that have reading skills at or below the eighth grade level. Suppose a sample of 1537 tenth graders is drawn. Of the students sampled, 1184 read above the eighth grade level. Using the data, construct the 95% confidence interval for the population proportion of tenth graders reading at or below the eighth grade level.
Answer:
The 95% confidence interval for the population proportion of tenth graders reading at or below the eighth grade level is (0.2087, 0.2507).
Step-by-step explanation:
In a sample with a number n of people surveyed with a probability of a success of [tex]\pi[/tex], and a confidence level of [tex]1-\alpha[/tex], we have the following confidence interval of proportions.
[tex]\pi \pm z\sqrt{\frac{\pi(1-\pi)}{n}}[/tex]
In which
z is the zscore that has a pvalue of [tex]1 - \frac{\alpha}{2}[/tex].
For this problem, we have that:
Suppose a sample of 1537 tenth graders is drawn. Of the students sampled, 1184 read above the eighth grade level. So 1537 - 1184 = 353 read at or below this level. Then
[tex]n = 1537, \pi = \frac{353}{1537} = 0.2297[/tex]
95% confidence level
So [tex]\alpha = 0.05[/tex], z is the value of Z that has a pvalue of [tex]1 - \frac{0.05}{2} = 0.975[/tex], so [tex]Z = 1.96[/tex].
The lower limit of this interval is:
[tex]\pi - z\sqrt{\frac{\pi(1-\pi)}{n}} = 0.2297 - 1.96\sqrt{\frac{0.2297*0.7703}{1537}} = 0.2087[/tex]
The upper limit of this interval is:
[tex]\pi + z\sqrt{\frac{\pi(1-\pi)}{n}} = 0.2297 + 1.96\sqrt{\frac{0.2297*0.7703}{1537}} = 0.2507[/tex]
The 95% confidence interval for the population proportion of tenth graders reading at or below the eighth grade level is (0.2087, 0.2507).
Which of these fractions is an improper fraction? 5/3 or 3/5
Answer:
5/3 is an improper fraction because 5 is higher then 3. So the correct way of writing it would be 1 2/3.
Step-by-step explanation:
Lard-O potato chips guarantees that all snack-sized bags of chips are between 16 and 17 ounces. The machine that fills the bags has an output with a mean of 16.5 and a standard deviation of 0.25 ounces. Construct a control chart for the Lard-O example using 3 sigma limits if samples of size 5 are randomly selected from the process. The center line is ____. The standard deviation of the sample mean is ____. The UCL
Answer:
- The center line is at 16.5 ounces.
- The standard deviation of the sample mean = 0.112 ounce.
- The UCL = 16.836 ounces.
- The LCL = 16.154 ounces.
Step-by-step explanation:
The Central limit theorem allows us to write for a random sample extracted from a normal population distribution with each variable independent of one another that
Mean of sampling distribution (μₓ) is approximately equal to the population mean (μ).
μₓ = μ = 16.5 ounces
And the standard deviation of the sampling distribution is given as
σₓ = (σ/√N)
where σ = population standard deviation = 0.25 ounce
N = Sample size = 5
σₓ = (0.25/√5) = 0.1118033989 = 0.112 ounce
Now using the 3 sigma limit rule that 99.5% of the distribution lies within 3 standard deviations of the mean, the entire distribution lies within
(μₓ ± 3σₓ)
= 16.5 ± (3×0.112)
= 16.5 ± (0.336)
= (16.154, 16.836)
Hope this Helps!!!
for a sample size of 115 and a population parameter of 0.1,what is the standard deviation of the normal curve that can be used to approximate the binomial probability histogram. Round your answer to three decimal places
A.0.028
B.0.054
C.0.043
D.0.035
Answer:
A) 0.028
Step-by-step explanation:
Given:
Sample size, n = 115
Population parameter, p = 0.1
The X-Bin(n=155, p=0.1)
Required:
Find the standard deviation of the normal curve that can be used to approximate the binomial probability histogram.
To find the standard deviation, use the formula below:
[tex]\sigma = \sqrt{\frac{p(1-p)}{n}}[/tex]
Substitute figures in the equation:
[tex]\sigma = \sqrt{\frac{0.1(1 - 0.1)}{115}}[/tex]
[tex]\sigma = \sqrt{\frac{0.1 * 0.9}{115}}[/tex]
[tex]\sigma = \sqrt{\frac{0.09}{115}}[/tex]
[tex] \sigma = \sqrt{7.826*10^-^4}[/tex]
[tex] \sigma = 0.028 [/tex]
The Standard deviation of the normal curve that can be used to approximate the binomial probability histogram is 0.028
HURRY TIMEDD!!!!!
What is the value of the discriminant, b2 − 4ac, for the quadratic equation 0 = x2 − 4x + 5, and what does it mean about the number of real solutions the equation has? The discriminant is −4, so the equation has 2 real solutions. The discriminant is −4, so the equation has no real solutions. The discriminant is 35, so the equation has 2 real solutions. The discriminant is 35, so the equation has no real solutions.
Answer:
Second option is the correct choice.
Step-by-step explanation:
"The discriminant is −4, so the equation has no real solutions."
[tex]x^2-4x+5=0\\\\a=1,\:b=-4,\:c=5:\\\\b^2-4ac=\left(-4\right)^2-4\cdot \:1\cdot \:5=-4[/tex]
Best Regards!
Answer: B
The discriminant is −4, so the equation has no real solutions.
Step-by-step explanation:
Just took quiz EDG2021
Mark Brainliest
In a certain community, eight percent of all adults over age 50 have diabetes. If a health service in this community correctly diagnosis 95% of all persons with diabetes as having the disease and incorrectly diagnoses ten percent of all persons without diabetes as having the disease, find the probabilities that:
Complete question is;
In a certain community, 8% of all people above 50 years of age have diabetes. A health service in this community correctly diagnoses 95% of all person with diabetes as having the disease, and incorrectly diagnoses 10% of all person without diabetes as having the disease. Find the probability that a person randomly selected from among all people of age above 50 and diagnosed by the health service as having diabetes actually has the disease.
Answer:
P(has diabetes | positive) = 0.442
Step-by-step explanation:
Probability of having diabetes and being positive is;
P(positive & has diabetes) = P(has diabetes) × P(positive | has diabetes)
We are told 8% or 0.08 have diabetes and there's a correct diagnosis of 95% of all the persons with diabetes having the disease.
Thus;
P(positive & has diabetes) = 0.08 × 0.95 = 0.076
P(negative & has diabetes) = P(has diabetes) × (1 –P(positive | has diabetes)) = 0.08 × (1 - 0.95)
P(negative & has diabetes) = 0.004
P(positive & no diabetes) = P(no diabetes) × P(positive | no diabetes)
We are told that there is an incorrect diagnoses of 10% of all persons without diabetes as having the disease
Thus;
P(positive & no diabetes) = 0.92 × 0.1 = 0.092
P(negative &no diabetes) =P(no diabetes) × (1 –P(positive | no diabetes)) = 0.92 × (1 - 0.1)
P(negative &no diabetes) = 0.828
Probability that a person selected having diabetes actually has the disease is;
P(has diabetes | positive) =P(positive & has diabetes) / P(positive)
P(positive) = 0.08 + P(positive & no diabetes)
P(positive) = 0.08 + 0.092 = 0.172
P(has diabetes | positive) = 0.076/0.172 = 0.442
Using formula:
[tex]P(\text{diabetes diagnosis})\\[/tex]:
[tex]=\text{P(having diabetes and have been diagnosed with it)}\\ + \text{P(not have diabetes and yet be diagnosed with diabetes)}[/tex]
[tex]=0.08 \times 0.95+(1-0.08) \times 0.10 \\\\=0.08 \times 0.95+0.92 \times 0.10 \\\\=0.076+0.092\\\\=0.168[/tex]
[tex]\text{P(have been diagnosed with diabetes)}[/tex]:
[tex]=\frac{\text{P(have diabetic and been diagnosed as having insulin)}}{\text{P(diabetes diagnosis)}}[/tex]
[tex]=\frac{0.08\times 0.95}{0.168} \\\\=\frac{0.076}{0.168} \\\\=0.452\\[/tex]
Learn more about the probability:
brainly.com/question/18849788
What is AB? Geometry help please
Answer:
AB = 37 units.
Step-by-step explanation:
Solve for AB using the Pythagorean theorem:
c² = a² + b² (c being AB in this instance)
Plug in the values of the legs of the triangle:
c² = 12² + 35²
c² = 144 + 1225
c² = 1369
c = √1369
c = 37
Therefore, AB = 37.
Find the volume of a right circular cone that has a height of 4.2m and a base with a radius of 3.4m
Answer:
about 50.8 cubic meters
Step-by-step explanation:
The formula for the volume of a cone is ...
V = (1/3)πr²h
Put the given values into the formula and do the arithmetic.
V = (1/3)π(3.4 m)²(4.2 m) = 16.194π m³
__
For π to calculator precision, this is ...
V ≈ 50.84 m³
For π = 3.14, this is ...
V ≈ 50.82 m³
An article reports that 1 in 500 people carry the defective gene that causes inherited colon cancer. In a sample of 2000 individuals, what is the approximate distribution of the number who carry this gene
Answer:
Brianliest!
Step-by-step explanation:
4
1 in 500
500 x 4 = 2000
4 in 2000
What is the relative change from 6546 to 4392
Answer:
The relative change from 6546 and 4392 is 49.04
Step-by-step explanation:
How many units of insulin are in 0.75 ML a regular U – 100 insulin
Answer:
0.75 ML of insulin contains 75 units of insulin
Step-by-step explanation:
U - 100 insulin hold 100 units of insulin per ml
This means that:
1 ML = 100 units
∴ 0.75 ML = 100 × 0.75 = 75 units
Therefore 0.75 ML of insulin contains 75 units of insulin
a) find the value of 2x+y wehn x =4 and y =3 b) find the value of a^2 + b when a = -2 and b = 5
Answer:
a. 11b. 9Solution,
a. Given,
X=4
y=3
Now,
[tex]2x + y \\ = 2 \times 4 + 3 \\ = 8 + 3 \\ = 11[/tex]
b. Given,
a=-2
b=5
Now,
[tex] {a}^{2} + b \\ = {( - 2)}^{2} + 5 \\ = 4 + 5 \\ = 9[/tex]
hope this helps...
Good luck on your assignment..
Which graph shows a function whose domain and range exclude exactly one value?
Answer:
C (the third graph)
Step-by-step explanation:
This graph's function has a domain and range that both exclude one value, which is 0. The x and y values are never 0 in the function, as it approaches 0 but never meets it.
Answer:
see below
Step-by-step explanation:
This graph has an asymptote at y = 0 and x=0
This excludes these values
The domain excludes x =0
The range excludes y=0
√x+3 = √5x-1 Find the value of X
Answer:
x=1
Step-by-step explanation:
sqrt(x+3) = sqrt(5x-1)
Square each side
x+3 = 5x-1
Subtract x from each side
3 = 4x-1
Add 1 to each side
4 =4x
Divide by 4
x=1
Answer:
x= 1
Step-by-step explanation:
[tex]\sqrt{x+3}=\sqrt{5x-1}[/tex]
Square both sides.
x + 3 = 5x - 1
Subtract 3 and 5x on both sides.
x - 5x = -1 - 3
-4x = -4
Divide -4 into both sides.
-4x/-4 = -4/-4
x = 1
Find the volume of the cone.
4 cm
3 cm
V = [?] cm3
Round to the nearest tenth.
Answer:
Volume of a cone = 1/3πr²h
h = height
r = radius
r = 3cm h = 4cm
Volume = 1/3π(3)²(4)
= 36 × 1/3π
= 12π
= 36.69cm³
= 37cm³ to the nearest tenth
Hope this helps
Answer:
37.7
_______
NOT 37
Step-by-step explanation:
v = [tex]\frac{1}{3}[/tex] · [tex]\pi[/tex] · [tex]r^{2}[/tex] · [tex]h[/tex]
v = [tex]\frac{1}{3}[/tex] · [tex]\pi[/tex] · [tex]3^{2}[/tex] · [tex]4 = 12\pi = 37.69911 =[/tex] 37.7
A complex electronic system is built with a certain number of backup components in its subsystems. One subsystem has eight identical components, each with a probability of 0.45 of failing in less than 1,000 hours. The sub system will operate if any four of the eight components are operating. Assume that the components operate independently. (Round your answers to four decimal places.)
Required:
Find the probability that the subsystem operates longer than 1000 hours.
Answer:
0.7396 = 73.96% probability that the subsystem operates longer than 1000 hours.
Step-by-step explanation:
For each component, there are only two possible outcomes. Either they fail in less than 1000 hours, or they do not. The components operate independently. So we use the binomial probability distribution to solve this question.
Binomial probability distribution
The binomial probability is the probability of exactly x successes on n repeated trials, and X can only have two outcomes.
[tex]P(X = x) = C_{n,x}.p^{x}.(1-p)^{n-x}[/tex]
In which [tex]C_{n,x}[/tex] is the number of different combinations of x objects from a set of n elements, given by the following formula.
[tex]C_{n,x} = \frac{n!}{x!(n-x)!}[/tex]
And p is the probability of X happening.
Eight components:
This means that [tex]n = 8[/tex]
Probability of 0.45 of failing in less than 1,000 hours.
So 1 - 0.45 = 0.55 probability of working for longer than 1000 hours, which means that [tex]p = 0.55[/tex]
Find the probability that the subsystem operates longer than 1000 hours.
We need at least four of the components operating. So
[tex]P(X \geq 4) = P(X = 4) + P(X = 5) + P(X = 6) + P(X = 7) + P(X = 8)[/tex]
In which
[tex]P(X = x) = C_{n,x}.p^{x}.(1-p)^{n-x}[/tex]
[tex]P(X = 4) = C_{8,4}.(0.55)^{4}.(0.45)^{4} = 0.2627[/tex]
[tex]P(X = 5) = C_{8,5}.(0.55)^{5}.(0.45)^{3} = 0.2568[/tex]
[tex]P(X = 6) = C_{8,6}.(0.55)^{6}.(0.45)^{2} = 0.1569[/tex]
[tex]P(X = 7) = C_{8,7}.(0.55)^{7}.(0.45)^{1} = 0.0548[/tex]
[tex]P(X = 8) = C_{8,8}.(0.55)^{8}.(0.45)^{0} = 0.0084[/tex]
[tex]P(X \geq 4) = P(X = 4) + P(X = 5) + P(X = 6) + P(X = 7) + P(X = 8) = 0.2627 + 0.2568 + 0.1569 + 0.0548 + 0.0084 = 0.7396[/tex]
0.7396 = 73.96% probability that the subsystem operates longer than 1000 hours.
The promising alternative energy sources currently under development are fuel cell technology and large-scale solar energy power. The probabilities that these two sources will be successfully developed and commercially viable in the next 10 years are 0.70 and 0.85, respectively. The successful development of these two energy sources are statistically independent. Determine the following: a. The probability that there will be energy supplied by these two alternative sources in the next 10 years. b. The probability that only one of the two alternative energy sources will be commercially viable in the next 10 years.
Answer:
Step-by-step explanation:
a) Denote the event of commercially availability of f_uel cell technology as F_, commercial availability of solar power technology as S
Write the probability of energy supplied by these energy sources in the next 10 years
P(energy supplied) = P(S ∪ F) -----(1)
Rewrite eqn (1)
P(energy supplied) = P(S) + P(F) - P(F) P(S) ----(2)
substitute 0.85 for P(S) and 0,7 for P(F) in eqn (2) to find the probability of energy supplied by these energy sources
P(energy supplied) = 0.85 + 0.7 - (0.7 * 0.85)
= 0.85 + 0.7 - (0.595)
= 1.55 - 0.595
= 0.955
Therefore, the probability that there will be energy supplied by these two alternative sources in the next 10 years is 0.955
B) write the probability of only one source of energy available
P(only one source of energy available) = [tex]P(\bar F S)[/tex] ∪ [tex]P( \bar S F)[/tex] ---(3)
Rewrite the equation (3)
P(only one source of energy available) =
[tex]=P(\bar F S)+P(\bar S F)\\\\=\{[1-P(F)]P(S)+[1-P(S)]P(F)\}---(4)[/tex]
[tex]=\{[1-0.7]0.85+[1-0.85]0.7\}\\\\=0.255+0.105\\\\=0.36[/tex]
Therefore,The probability that only one of the two alternative energy sources will be commercially viable in the next 10 years is 0.36
13. Two points P and Q, 10 m apart on level ground,
are due West of the foot B of a tree TB. Given that
TPB = 23° and TQB = 32°, find the height of tree
Answer: height = 13.24 m
Step-by-step explanation:
Draw a picture (see image below), then set up the proportions to find the length of QB. Then input QB into either of the equations to find h.
Given: PQ = 10
∠TPB = 23°
∠TQB = 32°
[tex]\tan P=\dfrac{opposite}{adjacent}\qquad \qquad \tan Q=\dfrac{opposite}{adjacent}\\\\\\\tan 23^o=\dfrac{h}{10+x}\qquad \qquad \tan 32^o=\dfrac{h}{x}\\\\\\\underline{\text{Solve each equation for h:}}\\\tan 23^o(10+x)=h\qquad \qquad \tan 32^o(x)=h\\\\\\\underline{\text{Set the equations equal to each other and solve for x:}}\\\tan23^o(10+x)=\tan32^o(x)\\0.4245(10+x)=0.6249x\\4.245+0.4245x=0.6249x\\4.245=0.2004x\\21.18=x[/tex]
[tex]\underline{\text{In put x = 21.18 into either equation and solve for h:}}\\h=\tan 32^o(x)\\h=0.6249(2.118)\\\large\boxed{h=13.24}[/tex]