Answer:
(a) Probability distribution is prepared below.
(b) The probability that two or fewer heads are observed in three tosses is 0.875.
(c) The probability that at least one head is observed in three tosses is 0.875.
(d) The expected value of X is 1.5.
(e) The standard deviation of X is 2.121.
Step-by-step explanation:
The complete question is: A fair coin is tossed three times. Let X be the number of heads observed in three tosses of this fair coin.
(a) Find the probability distribution of X.
(b) Find the probability that two or fewer heads are observed in three tosses. (Round your answer to three decimal places.)
(c) Find the probability that at least one head is observed in three tosses. (Round your answer to three decimal places.)
(d) Find the expected value of X. (Round your answer to one decimal place.)
(e) Find the standard deviation of X. (Round your answer to three decimal places.)
Now, firstly the sample space obtained in three tosses of a fair coin is given as;
Sample Space (S) = {HHH, HHT, HTH, THH, HTT, TTH, THT, TTT}
(a) The Probability distribution of X is given below;
Number of Heads (X) P(X) [tex]X \times P(X)[/tex] [tex]X^{2} \times P(X)[/tex]
0 [tex]\frac{1}{8}[/tex] = 0.125 0 0
1 [tex]\frac{3}{8}[/tex] = 0.375 0.375 0.375
2 [tex]\frac{3}{8}[/tex] = 0.375 0.75 3
3 [tex]\frac{1}{8}[/tex] = 0.125 0.375 3.375
Total 1.5 6.75
(b) The probability that two or fewer heads are observed in three tosses is given by = P(X [tex]\leq[/tex] 2)
P(X [tex]\leq[/tex] 2) = P(X = 0) + P(X = 1) + P(X = 2)
= 0.125 + 0.375 + 0.375
= 0.875
(c) The probability that at least one head is observed in three tosses is given by = P(X [tex]\geq[/tex] 1)
P(X [tex]\geq[/tex] 1) = 1 - P(X = 0)
= 1 - 0.125
= 0.875
(d) The expected value of X = E(X) = [tex]\sum (X \times P(X))[/tex]
= 1.5
(e) The Variance of X = V(X) = [tex]E(X^{2} ) - ( E(X))^{2}[/tex]
= [tex]\sum (X^{2} \times P(X))- (\sum (X \times P(X)))^{2}[/tex]
= [tex]6.75 - 1.5^{2}[/tex] = 4.5
Now, Standard deviation of X = [tex]\sqrt{V(X)}[/tex]
= [tex]\sqrt{4.5}[/tex] = 2.121.
If a procedure meets all the conditions of a binomial distribution except that the number of trials is not fixed, then the geometric distribution can be used. The probability of getting the first success on the xth trial is given by
P
(
x
)
=
p
(
1
−
p
)
x
−
1
where
p
is the probability of success on any one trial.
Assume that the probability of a defective computer component is 0.21. Find the probability that the first defect is found in the fifth component tested.
(Round answer to four decimal places.)
P
(
5
)
=
Answer:
M.
Step-by-step explanation:
If f(x) = (-x)^3, what is f(-2)?
-6
-8
8
6
Answer:
The answer is 8
Step-by-step explanation:
Plug -2 in for x. The double-negative inside the parenthesis makes it positive, then do the exponent.
Answer:
-(-2)^3 = 2^3 = 8
Answer is C
Step-by-step explanation:
So we plug in the numbers. We have -2 as x. (-(-2)^3 would be our thing. Thats because our x is the negative so the negative of -2 is 2.
2^3 = 8
therefore its 8
Please help. I’ll mark you as brainliest if correct!!!!!
[tex]x^2+14x+40=0\\x^2+14x+40+9-9=0\\x^2+14x+49=9\\(x+7)^2=9\\\\D=7\\E=9[/tex]
Answer:
x^2+14x+40=0\\x^2+14x+40+9-9=0\\x^2+14x+49=9\\(x+7)^2=9\\\\D=7\\E=9
Step-by-step explanation:
Assignment
Use the function f(x) = 2x3 - 3x2 + 7 to complete the exercises.
f(-1) =
f(1) =
f(2)=
>
Answer:
The value of the function f(x) at x=a can be determined by substituting a instead of x into the function expression.
1. When x=-1, then
f(-1) = 2 * (-1)^3 - 3 * (-1)^2 + 7 = -2 - 3 + 7 = 2.
2. When x=1, then
f(1) = 2 * 1^3 - 3 * 1^2 + 7 = 2 - 3 + 7 = 6.
3. When x=2, then
f(-1) = 2 * 2^3 - 3 * 2^2 + 7 = 16 - 12 + 7 = 11.
Step-by-step explanation:
Answer:
f(−1) =✔ 2
f(1) = ✔ 6
f(2) =✔ 11
Step-by-step explanation:
what is 2/3 of 460? Just a little easy one for points
Answer:
2/3 * 460 = 306 and 2/3
Multiply 460 by 2/3 by first multiplying 460 by 2, then divide that by 3:
460 x 2 = 920
920 /3 = 306 2/3
The answer is 306 2/3
Can someone plz help me solved this problem I need help ASAP plz help me! Will mark you as brainiest!
Answer:
8
Step-by-step explanation:
y²+by+16= (y+4)²
y²+by+16= y²+2*4*y+4²
y²+by+16= y²+8y+16
by=8y
b=8
Solve for x: 3x - 5 = 2x + 6.
Your answer
Answer:
3x-5=2x+6
x-5=6
x=11
Select all of the following statements that are true:
A. Random samples only generate unbiased estimates of long-run proportions, not long-run means.
B. You shouldnt take a random sample of more than 5% of the population size.
C. There is no way that a random sample of 100 people can be representative of all adults living in the United States.
D. If this question is voted out, the alternate option is "larger samples are always better than smaller samples, regardless of how the sample was collected."
E. Nonrandom samples are always poor representations of the population
Answer:
B. You shouldnt take a random sample of more than 5% of the population size.
Step-by-step explanation:
B. You shouldnt take a random sample of more than 5% of the population size. This is True, so as to avoid the research analysis to be more complex to interpret and analyzed
However, the following are not true statements:
A. Random samples only generate unbiased estimates of long-run proportions, not long-run means. This is False, as there may be sampling error, when picking the sample, which will lead to bias estimates in the long run proportions
C. There is no way that a random sample of 100 people can be representative of all adults living in the United States. This is False, as using the right factors such as gender, age, income, etc, in selecting the sample, 100 people is enough to use as sample of adults living in the United States
D. If this question is voted out, the alternate option is "larger samples are always better than smaller samples, regardless of how the sample was collected." This is False, larger samples are not always better than smaller samples. In fact, they are often difficult to analyze and interpret.
E. Nonrandom samples are always poor representations of the population: This is False, depending on the expected outcome of the research study. Some research studies required the research to use Nonrandom samples to reach verifiable conclusion.
A classic counting problem is to determine the number of different ways that the letters of "misspell" can be arranged. Find that number.
Answer:
10,080 different ways that the letters of "misspell" can be arranged.
Step-by-step explanation:
Number of arrangents of the letters of a word:
A word has n letters.
The are m repeating letters, each of them repeating [tex]r_{0}, r_{1}, ..., r_{m}[/tex] times
So the number of distincts ways the letters can be arranged is:
[tex]N_{A} = \frac{n!}{r_{1}! \times r_{2}! \times ... \times r_{m}}[/tex]
In this question:
Misspell has 8 letters, with s and l repeating twice.
So
[tex]N_{A} = \frac{8!}{2!2!} = 10080[/tex]
10,080 different ways that the letters of "misspell" can be arranged.
A certain test preparation course is designed to help students improve their scores on the LSAT exam. A mock exam is given at the beginning and end of the course to determine the effectiveness of the course. The following measurements are the net change in 4 students' scores on the exam after completing the course: 12,7,13,11 Using these data, construct a 80% confidence interval for the average net change in a student's score after completing the course. Assume the population is approximately normal. Step 3 of 4 : Find the critical value that should be used in constructing the confidence interval. Round your answer to three decimal places.
Answer:
The 80% confidence interval for the average net change is (8.596, 12.904).
Critical value t=1.638.
Step-by-step explanation:
First, we calculate the mean and standard deviation of the sample:
[tex]M=\dfrac{1}{n}\sum_{i=1}^n\,x_i\\\\\\M=\dfrac{1}{4}(12+7+13+11)\\\\\\M=\dfrac{43}{4}\\\\\\M=10.75\\\\\\s=\dfrac{1}{n-1}\sum_{i=1}^n\,(x_i-M)^2\\\\\\s=\dfrac{1}{3}((12-10.75)^2+(7-10.75)^2+(13-10.75)^2+(11-10.75)^2)\\\\\\s=\dfrac{20.75}{3}\\\\\\s=6.92\\\\\\[/tex]
We have to calculate a 80% confidence interval for the mean.
The population standard deviation is not known, so we have to estimate it from the sample standard deviation and use a t-students distribution to calculate the critical value.
The sample mean is M=10.75.
The sample size is N=4.
When σ is not known, s divided by the square root of N is used as an estimate of σM:
[tex]s_M=\dfrac{s}{\sqrt{N}}=\dfrac{2.63}{\sqrt{4}}=\dfrac{2.63}{2}=1.315[/tex]
The degrees of freedom for this sample size are:
[tex]df=n-1=4-1=3[/tex]
The t-value for a 80% confidence interval and 3 degrees of freedom is t=1.638.
The margin of error (MOE) can be calculated as:
[tex]MOE=t\cdot s_M=1.638 \cdot 1.315=2.154[/tex]
Then, the lower and upper bounds of the confidence interval are:
[tex]LL=M-t \cdot s_M = 10.75-2.154=8.596\\\\UL=M+t \cdot s_M = 10.75+2.154=12.904[/tex]
The 80% confidence interval for the average net change is (8.596, 12.904).
The radius of a circle is 5 cm. Find its area to the nearest tenth.
Answer:
78.5 cm^2
Step-by-step explanation:
The area of a circle is found by
A = pi r^2
A = pi (5)^2
A = 25pi
Letting pi = 3.14
A = 25(3.14)
A =78.5 cm^2
Letting pi be the pi button
A =78.53981634
Rounding to the nearest tenth
78.5
Answer:
78.5 cm²
Step-by-step explanation:
The area of a circle can be found using the following formula.
a=πr²
We know the radius of the circle is 5 centimeters.
r=5
Substitute 5 in for r.
a=π(5²)
Evaluate the exponent. 5² is equal to 5*5, which equals 25.
a=π(25)
Multiply 25 and pi
a=78.5398163397
Round to the nearest tenth. The 3 in the hundredth place tells use to leave the 5 in the tenths place as is.
a≈78.5
Add appropriate units. Area always uses units², and the units in this case are centimeters.
a≈78.5 centimeters²
The area of the circle is about 78.5 square centimeters.
Claim: The mean pulse rate (in beats per minute) of adult males is equal to 69.3 bpm. For a random sample of 140 adult males, the mean pulse rate is 69.8 bpm and the standard deviation is 11.2 bpm. Complete parts (a) and (b) below.
a. Express the original claim in symbolic form.
_,_,bpm
Answer:
Part a
Null hypothesis: [tex] \mu = 69.3[/tex]
Alternative hypothesis: [tex]\mu \neq 69.3[/tex]
Part b
[tex] z = \frac{69.8- 69.3}{\frac{11.2}{\sqrt{140}}}= 0.528[/tex]
Step-by-step explanation:
For this case we have the following info given :
[tex] \bar X = 69.8[/tex] the sample mean
[tex] n= 140[/tex] represent the sample size
[tex] s = 11.2[/tex] represent the standard deviation
Part a
And we want to test if the true mean is equal to 69.3 so then the system of hypothesis:
Null hypothesis: [tex] \mu = 69.3[/tex]
Alternative hypothesis: [tex]\mu \neq 69.3[/tex]
Part b: Find the statistic
The statistic is given by:
[tex] z= \frac{\bar X - \mu}{\frac{\sigma}{\sqrt{n}}}[/tex]
And replacing the info we got:
[tex] z = \frac{69.8- 69.3}{\frac{11.2}{\sqrt{140}}}= 0.528[/tex]
What is the value of Y ? I’ll give you a brainslist !!!
[tex]answer \\ = 5 \sqrt{3} \\ please \: see \: the \: attached \: picture \: for \: \: full \: solution \\ hope \: it \: helps[/tex]
Answer:
[tex]5 \sqrt{3} [/tex]
First answer is correct
Step-by-step explanation:
[tex] \frac{5}{x} = \cos(60) \\ \frac{5}{x} = \frac{1}{2} \\ x = 10 \\ \frac{y}{x} = \sin(60 ) \\ \frac{y}{10} = \frac{ \sqrt{3} }{2} \\ 2y = 10 \sqrt{3} \\ y = \frac{10 \sqrt{3} }{2} \\ y = 5 \sqrt{3} [/tex]
hope this helps
brainliest appreciated
good luck! have a nice day!
what is the radius of the circle that has an area of [tex]81*x*pi[/tex] degrees
Answer:
R=9
Step-by-step explanation:
the formula for area of a circle is pi r squared
where r denotes the radius of the circle
equating the formula for area with the area of the circle provided
p\i r squared = 81 p\i
r squared = 81
r = radical 81
r =9 inches
Based on the type of equations in the system, what is the greatest possible number of solutions? StartLayout Enlarged left-brace 1st Row x squared + y squared = 9 2nd row 9 x + 2 y = 16 EndLayout
Answer:
2
Step-by-step explanation:
Given the system of equations:
[Tex]x^2+y^2=9\\9x+2y=16[/tex]
Comparing [Tex]x^2+y^2=9[/tex] with the general standard equation of a circle [Tex](x-h)^2+(y-k)^2=r^2[/tex].
The first equation is an equation of a circle centred at (0,0) with a Radius of 3.
The second equation 9x+2y=16 is a straight line equation.
A straight line can only intersect a circle at a maximum of 2 points.
Therefore the greatest possible number of solutions to the equations in the system is 2.
Answer:
2
Step-by-step explanation:
and jj is gay of outer banks
Look at the row of numbers. What number should come next?
8, 4, 2, 1, 1/2, 1/4, ?
Answer:
1/8
Step-by-step explanation
Every time the number is divided by 2 like 8 divided by 2 is 4 and 4 divided by 2 is 2 and so on so if you divide 1/4 by 2 it would be 0.125 and that in fraction would be 1/8.
What is equivalent to
16x-12-24x+4
Answer:
-8x - 8
Step-by-step explanation:
You have to combine like term.
So you add 16x + -24x = -8x
And you add -12 + 4 = -8
Your answer would be -8x - 8
I hope this helps!
Shari wrote the numbers from 1 to 16 on a card.
Next, she crossed out all the numbers which are factors of 80.
Then, she crossed out all the numbers which are multiples of 3.
How many numbers were not crossed out?
Indicate which of the following situations inferential statistics: a. An annual stockholders' report details the assets of the corporation. b. A history instructor tells his class the number of students who received an A on a recent exam. c. The mean of a sample set of scores is calculated to characterize the sample. d. The sample data from a poll are used to estimate the opinion of the population. e. A correlational study is conducted on a sample to determine whether educational level and income in the population are related. f. A newspaper article reports the average salaries of federal employees from data collected on all federal employees.
Answer:
The situations c, d and e are Inferential statistics.
Step-by-step explanation:
Inferential statistics is used to determine reasons for a situation or phenomenon. It helps to draw conclusions grounded on extrapolations, and is hence fundamentally dissimilar from descriptive statistics that only summarizes the data that has truly been measured.
Descriptive statistics are short-term descriptive coefficients that condenses a given data set, which can be a demonstration of the whole or a sample of a whole population.
All descriptive statistics are either central tendency measure or variability measure. Measures of central tendency define the epicenter position of a distribution for a data set.
From the provided situations the Inferential statistics are:
c. The mean of a sample set of scores is calculated to characterize the sample.
d. The sample data from a poll are used to estimate the opinion of the population.
e. A correlational study is conducted on a sample to determine whether educational level and income in the population are related.
Thus, the situations c, d and e are Inferential statistics.
The one that demonstrates inferential statistics would be:
c). The mean of a sample set of scores is calculated to characterize the sample.
d). The sample data from a poll are used to estimate the opinion of the population.
e). A correlational study is conducted on a sample to determine whether the educational level and income in the population are related.
Inferential StatisticsInferential statistics is denoted as the kind of statistics that is concluded through a small sample employed which will act as the representative of the larger population.
The smaller sample's characteristics are analyzed and deductions are made in general about the entire population.
The above statements exemplify these characteristics by calculating the mean of the sample population and performing a correlational examination.
Thus, options c, d, and e are the correct answers.
Learn more about "Statistics" here:
brainly.com/question/14318705
Find the area of a circle with radius, r = 19cm.
Give your answer rounded to 3 SF.
A fraction with a zero in the numerator equals
Answer:Any legal fraction (denominator not equal to zero) with a numerator equal to zero has an overall value of zero. all have a fraction value of zero because the numerators are equal to zero.
Which table represents a relation that is not function
Please urgent
A rectangle has a length of 60 in and a width of 8 in. Given a scale factor of 4in:5ft. What is the area of the rectangle?
Answer:
750ft²
Step-by-step explanation:
Area of rectangle = L*B
Before we find the area of the given rectangle, we need to convert the dimensions using the given scale.
Thus, dimensions of the given rectangle using the scale factor of 4in:5ft would be:
==> Length = 60in = (60*5)/4 = 75ft
Breadth or Width = 8in = (8*5)/4 = 10ft
Therefore, area of rectangle = L * B
= 75ft * 10ft
= 750 ft²
Area of rectangle = 750ft²
Please answer this question I give brainliest thank you! Number 16
Answer:
4a
Step-by-step explanation:
The mean is found by adding all of the data set together and then dividing by the amount of individual pieces of data in the set.
(2+3+3+8) = 16
16/4=4
The answer is 4a.
WILL GIVE BRAINLIEST ANSWER ASAP
Answer:
x = -6
Step-by-step explanation:
-2/3x + 9 = 4/3x - 3
First we need to simplify to where we have x on one side and a constant (number not connected to a variable) on the other side.
Subtract 4/3x from both sides:
-2/3x + 9 - 4/3x = -3
-6/3x + 9 = -3
Now subtract 9 from both sides:
-6/3x + 9 - 9 = -3 - 9
-6/3x = -12
Now turn -6/3 into a whole number to make things more simple:
-6/3 = -2
-2x = -12
Now divide both sides by -2 to get x by itself
-2x/-2 = -12/-2
x = -6
Please answer this correctly
Answer:
540
Step-by-step explanation:
Since the surface area is 408, we can set up the equation
2*9*6 + 2*r*9 + 2*r*6 = 408
108 + 30r = 408
30r = 300
r = 10
The volume is length * width * height
9*6*10 = 540
Suppose that a random number generator randomly generates a number from 1 to 65. Once a specific number is generated, the generator will not select that number again until it is reset. If a person uses the random number generator 65 times in a row without resetting, how many different ways can the numbers be generated?
Answer:
65!
65! = 8. 2547650592 * 10^ 90 approximately
Step-by-step explanation:
A random number generator randomly generates a number from 1 to 65.
Once a specific number is generated, the generator will not select that number again until it is reset.
The number of ways it can be used is = 65!
65! = 8. 25476505* 10^ 90 approximately
The table shows ordered pairs of the function y=8-2x What is the value of y when x = 8?
Answer:-8
Step-by-step explanation:
8 - 2 × 8
8 - 16
-8
Find the mode for the following distribution.
Number Frequency
16
3
20
5
24
9
28
7
32
7
36
5
40
3
24
28
32
28 and 32
Answer:
28 and 32
Step-by-step explanation:
they have the most
Suppose that the raw daily oxygen purities delivered by an air-products supplier have a standard deviation LaTeX: \sigma\approx.1 σ ≈ .1 (percent), and it is plausible to think of daily purites as independent random variables. Approximate the probability that the sample mean LaTeX: \frac{ }{X} X of n = 25 delivered purities falls within .03 (percent) of the raw daily purity mean, LaTeX: \mu μ .
Answer:
There is a probability of 86.6% that the sample mean falls within 0.03 percent of the raw purity mean.
Step-by-step explanation:
We have a population standard deviation of σ ≈ 0.1.
We have a sample of size n=25.
Then, we have a sampling distribution, which has a standard deviation for the sample mean that is:
[tex]\sigma_s=\dfrac{\sigma}{\sqrt{n}}=\dfrac{0.1}{\sqrt{25}}=\dfrac{0.1}{5}=0.02[/tex]
Now, we can calculate a z-score for a deviation of 0.03 percent from the mean as:
[tex]z=\dfrac{X-\mu}{\sigma}=\dfrac{0.03}{0.02}=\dfrac{0.03}{0.02}=1.5[/tex]
Note: we considered that the margin is ±0.03.
Then, the probability is:
[tex]P(|X-\mu|<0.03\%)=P(|z|<1.5)=0.866[/tex]
