Answer:
40
Step-by-step explanation:
as 1st sq no is.4 and 2nd sq no. is 36
and their sum is =4+36
=40.....ans
Suppose that we want to generate the outcome of the flip of a fair coin, but that all we have at our disposal is a biased coin which lands on heads with some unknown probability p that need not be equal to1/2. Consider the following procedure for accomplishing our task:
1. Flip the coin.
2. Flip the coin again.
3. If both flips land on heads or both land on tails, return to step 1. 4. Let the result of the last flip be the result of the experiment.
(a) Show that the result is equally likely to be either heads or tails.
(b) Could we use a simpler procedure that continues to flip the coin until the last two flips are different and then lets the result be the outcome of the final flip?
Answer:
Step-by-step explanation:
Given that;
the following procedure for accomplishing our task are:
1. Flip the coin.
2. Flip the coin again.
From here will know that the coin is first flipped twice
3. If both flips land on heads or both land on tails, it implies that we return to step 1 to start again. this makes the flip to be insignificant since both flips land on heads or both land on tails
But if the outcomes of the two flip are different i.e they did not land on both heads or both did not land on tails , then we will consider such an outcome.
Let the probability of head = p
so P(head) = p
the probability of tail be = (1 - p)
This kind of probability follows a conditional distribution and the probability of getting heads is :
[tex]P( \{Tails, Heads\})|\{Tails, Heads,( Heads ,Tails)\})[/tex]
[tex]= \dfrac{P( \{Tails, Heads\}) \cap \{Tails, Heads,( Heads ,Tails)\})}{ {P( \{Tails, Heads,( Heads ,Tails)\}}}[/tex]
[tex]= \dfrac{P( \{Tails, Heads\}) }{ {P( \{Tails, Heads,( Heads ,Tails)\}}}[/tex]
[tex]= \dfrac{P( \{Tails, Heads\}) } { {P( Tails, Heads) +P( Heads ,Tails)}}[/tex]
[tex]=\dfrac{(1-p)*p}{(1-p)*p+p*(1-p)}[/tex]
[tex]=\dfrac{(1-p)*p}{2(1-p)*p}[/tex]
[tex]=\dfrac{1}{2}[/tex]
Thus; the probability of getting heads is [tex]\dfrac{1}{2}[/tex] which typically implies that the coin is fair
(b) Could we use a simpler procedure that continues to flip the coin until the last two flips are different and then lets the result be the outcome of the final flip?
For a fair coin (0<p<1) , it's certain that both heads and tails at the end of the flip.
The procedure that is talked about in (b) illustrates that the procedure gives head if and only if the first flip comes out tail with probability 1 - p.
Likewise , the procedure gives tail if and and only if the first flip comes out head with probability of p.
In essence, NO, procedure (b) does not give a fair coin flip outcome.
All the employees of ABC Company are assigned ID numbers. The ID number consists of the first letter of an employee's last name, followed by three numbers. (a) How many possible different ID numbers are there
Answer:
there will be 9 id no. which it contains
A ladder leans against the side of a house. The angle of elevation of the ladder is 66 degrees, and the top of the ladder is 15 ft above the ground. Find the distance from the bottom of the ladder to the side of the house. Round your answer to the nearest tenth.
Answer:
x ≈ 6.7 ft
Step-by-step explanation:
We are going to use tan∅ to find our answer:
tan66° = 15/x
xtan66° = 15
x = 15/tan66°
x = 6.67843 ft
f(x)=x^2 what is g(x)
Answer: D
Step-by-step explanation:
Sometimes, it is hard to see which function fits g(x). We are given the point (4,1). Luckily, the point lies on g(x). We can plug in (4,1) into the g(x) equations and see which best fits.
A. Incorrect
[tex]1=4(4)^2[/tex]
[tex]1=4(16)[/tex]
[tex]1\neq 64[/tex]
B. Incorrect
[tex]1=\frac{1}{4} (4)^2[/tex]
[tex]1=\frac{1}{4} (16)[/tex]
[tex]1\neq 4[/tex]
C. Incorrect
[tex]1=(\frac{1}{2}(4))^2[/tex]
[tex]1=(2)^2[/tex]
[tex]1\neq 4[/tex]
D. Correct
[tex]1=(\frac{1}{4}(4))^2[/tex]
[tex]1=(1)^2[/tex]
[tex]1=1[/tex]
In an office complex of 1110 employees, on any given day some are at work and the rest are absent. It is known that if an employee is at work today, there is an 77% chance that she will be at work tomorrow, and if the employee is absent today, there is a 54% chance that she will be absent tomorrow. Suppose that today there are 899 employees at work.
Required:
a. Find the transition matrix for this scenario.
b. Predict the number that will be at work five days from now.
c. Find the steady-state vector.
Answer:
B
Step-by-step explanation:
A researcher compares the effectiveness of two different instructional methods for teaching pharmacology. A sample of 63 students using Method 1 produces a testing average of 52.2. A sample of 93 students using Method 2 produces a testing average of 72.3. Assume that the population standard deviation for Method 1 is 15.92, while the population standard deviation for Method 2 is 17.96. Determine the 95% confidence interval for the true difference between testing averages for students using Method 1 and students using Method 2.
Answer:
The 95% confidence interval for the difference between means is (-25.5, -14.7).
Step-by-step explanation:
We have to calculate a 95% confidence interval for the difference between means.
The sample 1 (Method 1), of size n1=63 has a mean of 52.2 and a standard deviation of 15.92.
The sample 2 (Method 2), of size n2=93 has a mean of 72.3 and a standard deviation of 17.96.
The difference between sample means is Md=-20.1.
[tex]M_d=M_1-M_2=52.2-72.3=-20.1[/tex]
The estimated standard error of the difference between means is computed using the formula:
[tex]s_{M_d}=\sqrt{\dfrac{\sigma_1^2}{n_1}+\dfrac{\sigma_2^2}{n_2}}=\sqrt{\dfrac{15.92^2}{63}+\dfrac{17.96^2}{93}}\\\\\\s_{M_d}=\sqrt{4.023+3.468}=\sqrt{7.491}=2.74[/tex]
The critical t-value for a 95% confidence interval is t=1.975.
The margin of error (MOE) can be calculated as:
[tex]MOE=t\cdot s_{M_d}=1.975 \cdot 2.74=5.41[/tex]
Then, the lower and upper bounds of the confidence interval are:
[tex]LL=M_d-t \cdot s_{M_d} = -20.1-5.41=-25.5\\\\UL=M_d+t \cdot s_{M_d} = -20.1+5.41=-14.7[/tex]
The 95% confidence interval for the difference between means is (-25.5, -14.7).
What is the exponential form of log32187=7?
Answer:
[tex]3^{7} = 2187[/tex]
Step-by-step explanation:
The base of the log, 3, would be the base of the exponent. The =7 would be the exponent itself, so now we have [tex]3^7[/tex]. The log of 2187 would be the = for the exponential form, so we have [tex]3^7 = 2187[/tex] as our final answer.
Let the sample space be
S = 1, 2, 3, 4, 5, 6, 7, 8, 9, 10.
Suppose the outcomes are equally likely. Compute the probability of the event E = 1, 2.
Answer:
probability of the event E = 1/5
Step-by-step explanation:
We are given;
Sample space, S = {1, 2, 3, 4, 5, 6, 7, 8, 9, 10},
Number of terms in sample S is;
n(S) = 10
We are given the event; E = {1, 2}
Thus, number of terms in event E is;
n(E) = 2
Now, Probability = favorable outcomes/total outcomes
Thus, the probability of the event E is;
P(E) = n(E)/n(S)
P(E) = 2/10
P(E) = 1/5
A spotlight on the ground shines on a wall 12 m away. If a man 2 m tall walks from the spotlight toward the building at a speed of 1.4 m/s, how fast is the length of his shadow on the building decreasing when he is 4 m from the building?
Answer:
the length of his shadow on the building is decreasing at the rate of 0.525 m/s
Step-by-step explanation:
From the diagram attached below;
the man is standing at point D with his head at point E
During that time, his shadow on the wall is y = BC
ΔABC and Δ ADE are similar in nature; thus their corresponding sides have equal ratios; i.e
[tex]\dfrac{AD}{AB} = \dfrac{DE}{BC}[/tex]
[tex]\dfrac{8}{12} = \dfrac{2}{y}[/tex]
8y = 24
y = 24/8
y = 3 meters
Let take an integral look at the distance of the man from the building as x, therefore the distance from the spotlight to the man is 12 - x
∴
[tex]\dfrac{12-x}{12}=\dfrac{2}{y}[/tex]
[tex]1- \dfrac{1}{12}x = 2* \dfrac{1}{y}[/tex]
To find the derivatives of both sides ;we have:
[tex]- \dfrac{1}{12}dx = 2* \dfrac{1}{y^2}dy[/tex]
[tex]- \dfrac{1}{12} \dfrac{dx}{dt} = 2* \dfrac{1}{y^2} \dfrac{dy}{dt}[/tex]
During that time ;
[tex]\dfrac{dx}{dt }= 1.4 \ m/s[/tex] and y = 3
So; replacing the value into above ; we have:
[tex]-\dfrac{1}{12}(1.4) = - \dfrac{2}{9} \dfrac{dy}{dt}[/tex]
[tex]\dfrac{dy}{dt} = \dfrac{\dfrac{ 1.4} {12 } }{ \dfrac{2}{9}}[/tex]
[tex]\dfrac{dy}{dt} = {\dfrac{ 1.4} {12 } }*{ \dfrac{9}{2}}[/tex]
[tex]\dfrac{dy}{dt} =0.525 \ m/s[/tex]
Thus; the length of his shadow on the building is decreasing at the rate of 0.525 m/s
Find the equation of the line.
Use exact numbers.
y=
Answer:
y = 2x+4
Step-by-step explanation:
First we need to find the slope using two points
(-2,0) and (0,4)
m = (y2-y1)/(x2-x1)
m = (4-0)/(0--2)
= 4/+2
= 2
we have the y intercept which is 4
Using the slope intercept form of the line
y = mx+b where m is the slope and b is the y intercept
y = 2x+4
SOMEONE PLEASE HELP ME ASAP PLEASE!!!
Answer:
C =81.64 cm
Step-by-step explanation:
The circumference is given by
C = 2* pi *r
The radius is 13
C = 2 * 3.14 * 13
C =81.64 cm
Answer:
[tex]= 81.64cm \\ [/tex]
Step-by-step explanation:
[tex]c = 2\pi \: r \\ = 2 \times 3.14 \times 13 \\ = 81.64cm[/tex]
hope this helps
brainliest appreciated
good luck! have a nice day!
Write the expression in simplest form 3(5x) + 8(2x)
Answer:
31x[tex]solution \\ 3(5x) + 8(2x) \\ = 3 \times 5x + 8 \times 2x \\ = 15x + 16x \\ = 31x[/tex]
hope this helps...
Good luck on your assignment...
The expression [tex]3(5x) + 8(2x)[/tex] in simplest form is 31x.
To simplify the expression [tex]3(5x) + 8(2x)[/tex], we can apply the distributive property:
[tex]3(5x) + 8(2x)[/tex]
[tex]= 15x + 16x[/tex]
Combining like terms, we have:
[tex]15x + 16x = 31x[/tex]
Therefore, the expression [tex]3(5x) + 8(2x)[/tex] simplifies to [tex]31x.[/tex]
To learn more on Expressions click:
https://brainly.com/question/14083225
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pls answer i give brainliest explain why road tires have narrow tyres but off road bikes have wide tyres
Answer:
Step-by-step explanation:
Most road bikes and touring bikes have thinner tires, while mountain bikes have big fat tires. ... A firm thin tire on the asphalt surface won't flatten much. The less the tire flattens out on the bottom, the less surface area is in contact with the road. Less contact in this case means less friction, and more speed.
please mark brainliest
Differentiate with respect to x (and simplify): 2x(1-x)^3 I need to show working out. I will mark the best answer BRAINLIEST
Answer:
First of all expand the terms
2x(1-x)³ = 2x( 1 - 3x + 3x² - x³)
Multiply by 2x
You will get
2x - 6x² + 6x³ -2x⁴
Differentiate each of the terms using differentiation rules
You will get
2 - 12x + 18x² - 8x³
So the final answer is
- 8x³ + 18x² - 12x + 2
Hope this helps.
Please please help me!!
Given that TU=8x+11 and UV=12x−1, what are x, TU, UV, and TV?
Answer:
x = 3TU = UV = 35TV = 70Step-by-step explanation:
The question lacks the required diagram. Find the diagram attached.
From the diagram, it can be seen that point U is the midpoint of T and V. This means that TU = UV
Given TU=8x+11 and UV=12x−1
8x+11 = 12x -1
8x-12x = -1-11
-4x = -12
x = 3
Since TU = 8x+11
TU = 8(3)+11
TU = 24+11
TU = 35
Also UV = 12x-1
UV = 12(3)-1
UV = 36- 1
UV = 35
TV = TU+UV
TV = 35+35
TV = 70
What are the domain and range of f(x) = 2|x – 4|?
Answer:
Domain: All real numbers or (negative infinity, positive infinity)
Range: [0, positive infinity)
Step-by-step explanation:
Domain; Since all values of x would work for this equation, simply any number could be plugged in. That means the domain would stretch to infinity because there are an infinite amount of inputs and outputs
Range; Even though we have an infinite amount of domain, when we plug in a negative x, anything inside the absolute value will turn positive. Therefore, no output (y) value will ever go below zero, and we have [0, positive infinity).
AC =
Round your answer to the nearest hundredth.
с
6
B
40°
А
Answer:
5.03
Step-by-step explanation:
Answer:
5.03 = AC
Step-by-step explanation:
Since this is a right triangle, we can use trig functions
tan theta = opp/ adj
tan 40 = AC /6
6 tan 40 = AC
5.034597787 = AC
To the nearest hundredth
5.03 = AC
Please help me find Jebel dhanna in UAE map.
Answer:
The full name of the place is the "Danat Jebel Dhanna". The Jebel Dhanna is currently located in the Abu Dhabi. It is said that it is one of the most best beach in the UAE, they also say that it is the biggest resort, of course, with a bunch of hotels.
hope this helps ;)
best regards,
`FL°°F~` (floof)
(please help!) find x.
Answer:
x = 6√2
Step-by-step explanation:
It is a 45°45°90° triangle so you can use the ratio.
x : x√2
x = 6√2
Which equation represents the line that passes through points (1 -5) and (3 -17)
Answer:
6x-11
Step-by-step explanation:
m=y2-y1
x2-x1
-17--5 = -12
3-1. -2
The two negatives cancel ❌
m=12
2
Divide by 2
m=6
y=mx+b
-5= 6 (1) + b
-5= 6 + b
Subtract (6) from both sides
b= -11
The equation for the line is 6x -11
In a recent study on world happiness, participants were asked to evaluate their current lives on a scale from 0 to 10, where 0 represents the worst possible life and 10 represents the best possible life. The mean response was 5.6 with a standard deviation of 2.6. (a) What response represents the 85th percentile? (b) What response represents the 62nd percentile? (c) What response represents the first quartile?
Answer:
a) 8.2962
b) 6.3956
c) 3.845
Step-by-step explanation:
Z-score:
In a set with mean [tex]\mu[/tex] and standard deviation [tex]\sigma[/tex], the zscore of a measure X is given by:
[tex]Z = \frac{X - \mu}{\sigma}[/tex]
The Z-score measures how many standard deviations the measure is from the mean. After finding the Z-score, we look at the z-score table and find the p-value associated with this z-score. This p-value is the probability that the value of the measure is smaller than X, that is, the percentile of X. Subtracting 1 by the pvalue, we get the probability that the value of the measure is greater than X.
In this question, we have that:
[tex]\mu = 5.6, \sigma = 2.6[/tex]
(a) What response represents the 85th percentile?
This is X when Z has a pvalue of 0.85. So X when Z = 1.037.
[tex]Z = \frac{X - \mu}{\sigma}[/tex]
[tex]1.037 = \frac{X - 5.6}{2.6}[/tex]
[tex]X - 5.6 = 2.6*1.037[/tex]
[tex]X = 8.2962[/tex]
(b) What response represents the 62nd percentile?
This is X when Z has a pvalue of 0.62. So X when Z = 0.306.
[tex]Z = \frac{X - \mu}{\sigma}[/tex]
[tex]0.306 = \frac{X - 5.6}{2.6}[/tex]
[tex]X - 5.6 = 2.6*0.306[/tex]
[tex]X = 6.3956[/tex]
(c) What response represents the first quartile?
The first quartile is the 100/4 = 25th percentile. So this is X when Z has a pvalue of 0.25, so X when Z = -0.675.
[tex]Z = \frac{X - \mu}{\sigma}[/tex]
[tex]-0.675 = \frac{X - 5.6}{2.6}[/tex]
[tex]X - 5.6 = 2.6*(-0.675)[/tex]
[tex]X = 3.845[/tex]
Given a normal distribution with (mean) μ= 50 and (standard deviation) σ = 4, what is the probability that:__________.
a) x>43
b) x<42
c) x>57.5
d) 42
e) x<40 or x>55
f) 5% of the values are less than what X value?
g) 60% of the values are between what two X values (symmetrically distributed around the mean)?
h) 85% of the values will be above what X value?
Answer:
a) P(x > 43) = 0.9599
b) P(x < 42) = 0.0228
c) P(x > 57.5) = 0.03
d) P(x = 42) = 0.
e) P(x<40 or x>55) = 0.1118
f) 43.42
g) Between 46.64 and 53.36.
h) Above 45.852.
Step-by-step explanation:
When the distribution is normal, we use the z-score formula.
In a set with mean [tex]\mu[/tex] and standard deviation [tex]\sigma[/tex], the zscore of a measure X is given by:
[tex]Z = \frac{X - \mu}{\sigma}[/tex]
The Z-score measures how many standard deviations the measure is from the mean. After finding the Z-score, we look at the z-score table and find the p-value associated with this z-score. This p-value is the probability that the value of the measure is smaller than X, that is, the percentile of X. Subtracting 1 by the pvalue, we get the probability that the value of the measure is greater than X.
In this question, we have that:
[tex]\mu = 50, \sigma = 4[/tex]
a) x>43
This is 1 subtracted by the pvalue of Z when X = 43. So
[tex]Z = \frac{X - \mu}{\sigma}[/tex]
[tex]Z = \frac{43 - 50}{4}[/tex]
[tex]Z = -1.75[/tex]
[tex]Z = -1.75[/tex] has a pvalue of 0.0401
1 - 0.0401 = 0.9599
P(x > 43) = 0.9599
b) x<42
This is the pvalue of Z when X = 42.
[tex]Z = \frac{X - \mu}{\sigma}[/tex]
[tex]Z = \frac{42 - 50}{4}[/tex]
[tex]Z = -2[/tex]
[tex]Z = -2[/tex] has a pvalue of 0.0228
P(x < 42) = 0.0228
c) x>57.5
This is 1 subtracted by the pvalue of Z when X = 57.5. So
[tex]Z = \frac{X - \mu}{\sigma}[/tex]
[tex]Z = \frac{57.5 - 50}{4}[/tex]
[tex]Z = 1.88[/tex]
[tex]Z = 1.88[/tex] has a pvalue of 0.97
1 - 0.97 = 0.03
P(x > 57.5) = 0.03
d) P(x = 42)
In the normal distribution, the probability of an exact value is 0. So
P(x = 42) = 0.
e) x<40 or x>55
x < 40 is the pvalue of Z when X = 40. So
[tex]Z = \frac{X - \mu}{\sigma}[/tex]
[tex]Z = \frac{40 - 50}{4}[/tex]
[tex]Z = -2.5[/tex]
[tex]Z = -2.5[/tex] has a pvalue of 0.0062
x > 55 is 1 subtracted by the pvalue of Z when X = 55. So
[tex]Z = \frac{X - \mu}{\sigma}[/tex]
[tex]Z = \frac{55 - 50}{4}[/tex]
[tex]Z = 1.25[/tex]
[tex]Z = 1.25[/tex] has a pvalue of 0.8944
1 - 0.8944 = 0.1056
0.0062 + 0.1056 = 0.1118
P(x<40 or x>55) = 0.1118
f) 5% of the values are less than what X value?
X is the 5th percentile, which is X when Z has a pvalue of 0.05, so X when Z = -1.645.
[tex]Z = \frac{X - \mu}{\sigma}[/tex]
[tex]-1.645 = \frac{X - 50}{4}[/tex]
[tex]X - 50 = -1.645*4[/tex]
[tex]X = 43.42[/tex]
43.42 is the answer.
g) 60% of the values are between what two X values (symmetrically distributed around the mean)?
Between the 50 - (60/2) = 20th percentile and the 50 + (60/2) = 80th percentile.
20th percentile:
X when Z has a pvalue of 0.2. So X when Z = -0.84.
[tex]Z = \frac{X - \mu}{\sigma}[/tex]
[tex]-0.84 = \frac{X - 50}{4}[/tex]
[tex]X - 50 = -0.84*4[/tex]
[tex]X = 46.64[/tex]
80th percentile:
X when Z has a pvalue of 0.8. So X when Z = 0.84.
[tex]Z = \frac{X - \mu}{\sigma}[/tex]
[tex]0.84 = \frac{X - 50}{4}[/tex]
[tex]X - 50 = 0.84*4[/tex]
[tex]X = 53.36[/tex]
Between 46.64 and 53.36.
h) 85% of the values will be above what X value?
Above the 100 - 85 = 15th percentile, which is X when Z has a pvalue of 0.15. So X when Z = -1.037.
[tex]Z = \frac{X - \mu}{\sigma}[/tex]
[tex]-1.037 = \frac{X - 50}{4}[/tex]
[tex]X - 50 = -1.037*4[/tex]
[tex]X = 45.852[/tex]
Above 45.852.
You are given an n×n board, where n is an even integer and 2≤n≤30. For how many such boards is it possible to cover the board with T-shaped tiles like the one shown? Each cell of the shape is congruent to one cell on the board.
Answer:
7
Step-by-step explanation:
The number of cells in a tile is 4. If colored alternately, there are 3 of one color and 1 of the alternate color. To balance the coloring, an even number of tiles is needed. Hence the board dimensions must be multiples of 4.
In the given range, there are 7 such boards:
4×4, 8×8, 12×12, 16×16, 20×20, 24×24, and 28×28
It is known that the number of hours a student sleeps per night has a normal distribution. The sleeping time in hours of a random sample of 8 students is given below. See Attached Excel for Data. Compute a 98% confidence interval for the true mean time a student sleeps per night and fill in the blanks appropriately. We have 98 % confidence that the true mean time a student sleeps per night is between and hours. (round to 3 decimal places)
Answer:
Step-by-step explanation:
The question is incomplete. The complete question is:
It is known that the number of hours a student sleeps per night has a normal distribution. The sleeping time in hours of a random sample of 8 students is given below. 7.4, 6.2, 8.5, 6.3, 5.4, 5.5, 6.3, 8.3 Compute a 98% confidence interval for the true mean time a student sleeps per night and fill in the blanks appropriately. We have 98% confidence that the true mean time a student sleeps per night is between _____ and ____ hours. (Keep 3 decimal places)
Solution:
Mean = (7.4 + 6.2 + 8.5 + 6.3 + 5.4 + 5.5 + 6.3 + 8.3)/8 = 6.7375
Standard deviation = √(summation(x - mean)²/n
Summation(x - mean)² = (7.4 - 6.7375)^2 + (6.2 - 6.7375)^2 + (8.5 - 6.7375)^2 + (6.3 - 6.7375)^2 + (5.4 - 6.7375)^2 + (5.5 - 6.7375)^2 + (6.3 - 6.7375)^2 + (8.3 - 6.7375)^2 = 9.97875
Standard deviation = √(9.97875/8
s = 1.12
Confidence interval is written in the form,
(Sample mean - margin of error, sample mean + margin of error)
The sample mean, x is the point estimate for the population mean.
Margin of error = z × s/√n
Where
sample standard deviation
number of samples
From the information given, the population standard deviation is unknown and the sample size is small, hence, we would use the t distribution to find the z score
In order to use the t distribution, we would determine the degree of freedom, df for the sample.
df = n - 1 = 8 - 1 = 7
Since confidence level = 98% = 0.98, α = 1 - CL = 1 - 0.98 = 0.02
α/2 = 0.02/2 = 0.01
the area to the right of z0.01 is 0.01 and the area to the left of z0.01 is 1 - 0.01 = 0.99
Looking at the t distribution table,
z = 2.998
Margin of error = 2.998 × 1.12/√8
= 1.19
the lower limit of this confidence interval is
6.738 - 1.19 = 5.548
the upper limit of this confidence interval is
6.738 + 1.19 = 7.928
We have 98 % confidence that the true mean time a student sleeps per night is between 5.548 hours and 7.928 hours.
Suppose the proportion X of surface area in a randomly selected quadrat that is covered by a certain plant has a standard beta distribution with α = 4 and β = 3.(a) Compute E(X) and V(X). (Round your answers to four decimal places.)E(X) = Correct: Your answer is correct.V(X) = Correct: Your answer is correct.(b) Compute P(X ≤ 0.5). (Round your answer to four decimal places.)
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.
The distribution of the number of hours of sleep people get per night is unimodal and symmetric with a mean of 6 hours and a standard deviation of 1.5. Using the Empirical Rule, approximately what percentage of people sleep between 6 and 7.5 hours per night
Answer:
Approximately 34% of people sleep between 6 and 7.5 hours per night
Step-by-step explanation:
The Empirical Rule states that, for a normally distributed random variable:
68% of the measures are within 1 standard deviation of the mean.
95% of the measures are within 2 standard deviation of the mean.
99.7% of the measures are within 3 standard deviations of the mean.
In this problem, we have that:
Mean = 6
Standard deviation = 1.5
The normal distribution is symmetric, which means that 50% of the measures are below the mean and 50% are above.
What percentage of people sleep between 6 and 7.5 hours per night
6 is the mean.
7.5 is 1 one standard deviation above the mean.
By the Empirical Rule, of the 50% of the measures that are above the mean, 68% are within 1 standard deviation of the mean(between 6 and 7.5).
0.5*0.68 = 0.34
Approximately 34% of people sleep between 6 and 7.5 hours per night
Which of the following is the graph of y = negative StartRoot x EndRoot + 1?
Answer:
see below
Step-by-step explanation:
y = -sqrt(x) +1
We know that the domain is from 0 to infinity
The range is from 1 to negative infinity
Answer:
b
Step-by-step explanation:
e2020
Timmy writes the equation f(x) - *x-1. He then doubles both of the terms on the right side to create the equation g(x) =
2x - 2. How does the graph of g(x) compare to the graph of f(x)?
The line of g(x) is steeper and has a higher y-intercept.
The line of g(x) is less steep and has a lower y-intercept.
The line of g(x) is steeper and has a lower y-intercept.
The line of g(x) is less steep and has a higher y-intercept.
Answer:
The line of g(x) is steeper and has a lower y-intercept.
Step-by-step explanation:
Doubling the function expands it vertically by a factor of 2. Everything is twice as far from the x-axis as it was. The line becomes steeper, and the y-intercept moves twice as far away. It was at -1, now is lower, at -2.
The line of g(x) is steeper and has a lower y-intercept.
UTGENT! I really need help, can anyone help me?
Answer:
x = 3.6
Step-by-step explanation:
By the Postulate of intersecting chords inside a circle.
[tex]x \times 5 = 3 \times 6 \\ 5x = 18 \\ x = \frac{18}{5} \\ x = 3.6 \\ [/tex]