Answer:
.0421
about 4.21%
Step-by-step explanation:
[tex]\frac{{8\choose3}}{{21\choose3}}=\frac{56}{1330}=.042105263[/tex]
Find a formula for the general term an of the sequence, assuming that the pattern of the first few terms continues. text({)1, 1/4, 1/16, 1/64, 1/256, ... text(})
Answer:
[tex]T_n = \frac{1}{4^{n-1}}[/tex]
Step-by-step explanation:
Given
[tex]({)1, 1/4, 1/16, 1/64, 1/256, ... (})[/tex]
Required
The general term
The given sequence is geometric.
So first, we calculate the common ratio (r)
[tex]r = T_2/T_1[/tex]
So, we have:
[tex]r = 1/4 \div 1[/tex]
[tex]r = 1/4[/tex]
The function is then calculated using:
[tex]T_n =T_1 * r^{n-1}[/tex]
This gives
[tex]T_n =1 * 1/4^{n-1}[/tex]
[tex]T_n = \frac{1}{4^{n-1}}[/tex]
A real estate agent has 12 properties that she shows. She feels that there is a 30% chance of selling any one property during a week. The chance of selling any one property is independent of selling another property. Compute the probability of selling no more than 2 properties in one week. Round your answer to four decimal places.
Answer:
0.2528 = 25.28% probability of selling no more than 2 properties in one week.
Step-by-step explanation:
For each property, there are only two possible outcomes. Either they are sold, or they are not. The chance of selling any one property is independent of selling another property, which means that the binomial probability distribution is used 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.
A real estate agent has 12 properties that she shows.
This means that [tex]n = 12[/tex]
She feels that there is a 30% chance of selling any one property during a week.
This means that [tex]p = 0.3[/tex]
Compute the probability of selling no more than 2 properties in one week.
2 or less sold, which is:
[tex]P(X \leq 2) = P(X = 0) + P(X = 1) + P(X = 2)[/tex]
In which
[tex]P(X = x) = C_{n,x}.p^{x}.(1-p)^{n-x}[/tex]
[tex]P(X = 0) = C_{12,0}.(0.3)^{0}.(0.7)^{12} = 0.0138[/tex]
[tex]P(X = 1) = C_{12,1}.(0.3)^{1}.(0.7)^{11} = 0.0712[/tex]
[tex]P(X = 2) = C_{12,2}.(0.3)^{2}.(0.7)^{10} = 0.1678[/tex]
Then
[tex]P(X \leq 2) = P(X = 0) + P(X = 1) + P(X = 2) = 0.0138 + 0.0712 + 0.1678 = 0.2528[/tex]
0.2528 = 25.28% probability of selling no more than 2 properties in one week.
In rural Ireland, a century ago, the students had to form a line. The student at the front of the line would be asked to spell a word. If he spelled it correctly, he was allowed to sit down. If not, he received a whack on the hand with a switch and was sent to the end of the line. Suppose the student could spell correctly 60% of the words in the lesson. What is the probability that the student would be able to sit down before receiving four whacks in the hand?
Answer:
The answer is "0.9102"
Step-by-step explanation:
P(student spell correct) = 0.6
P(student spell incorrect)=1-0.6=0.4
X=the pupil will be allowed to sit down after receiving three slaps on the hand Thus, X would assume Value
X=0 (student sit sans getting whacks)
X=1 (student sit down without receiving 1 whack) (student sit down without receiving 1 whack)
X=2 (student take a seat before receiving 2 whacks)
X=3 (student sit down after receiving 3 punches)
[tex]\to P(X)=0.6 \times 0.4^0 +0.6 \times 0.4 + 0.6 \times 0.4 ^2 + 0.6 \times 0.3^3[/tex]
[tex]=0.6 \times 1+0.24 + 0.6 \times 0.09 + 0.6 \times 0.027\\\\=0.6 +0.24 + 0.054 + 0.0162\\\\=0.9102\\\\[/tex]
Simplify
b. 3a + 4b-2a-b
4 나
V
216 x
Х
18
Answer:
a+3b
Step-by-step explanation:
3a+4b-2a-b
=3a-2a+4b-b
=a+3b
With the information that you gather from the summary tables, test the following (you can use excel when appropriate): Determine if there is sufficient evidence to conclude the average amount of births is over 5000 in the United States and territories at the 0.05 level of significance. Determine if there is sufficient evidence to conclude the average amount of deaths is equal to 6000 in the United States and territories at the 0.10 level of significance. Determine if there is sufficient evidence to conclude the average amount of marriages is greater or equal to 2500 in the United States and territories at the .05 level of significance. Determine if there is sufficient evidence to conclude the average amount of divorces is less than or equal to 4000 in the United States and territories at the 0.10 level of significance.
Answer:
Kindly check explanation
Step-by-step explanation:
A.)
H0 : μ = 5000
H0 : μ > 5000
xbar = 6671 ; s = 8185.21 ; n = 52 ; α = 0.05
The test statistic :
T = (xbar - μ) ÷ (s/√(n))
T = (6671 - 5000) ÷ (8185.21/√52)
T = 3.814
Pvalue from Test statistic : ; df = n - 1 = 52-1= 51
Pvalue at 3.814; 51 = 0.000185
Pvalue < α ; Reject H0 and conclude that average birth is greater than 5000
B)
H0 : μ = 6000
H0 : μ < 6000
xbar = 4187 ; s = 4386 ; n = 52 ; α = 0.01
The test statistic :
T = (xbar - μ) ÷ (s/√(n))
T = (4187 - 6000) ÷ (4386/√52)
T = - 2.981
Pvalue from Test statistic : ; df = n - 1 = 52-1= 51
Pvalue at - 2.981; 51 = 0.0022
Pvalue < α ; Reject H0 and conclude that average death is less than 6000
C.)
H0 : μ < 2500
H0 : μ ≥ 2500
xbar = 2744 ; s = 3134.41 ; n = 52 ; α = 0.05
The test statistic :
T = (xbar - μ) ÷ (s/√(n))
T = (2744 - 2500) ÷ (3134.41/√52)
T = 0.561
Pvalue from Test statistic : ; df = n - 1 = 52-1= 51
Pvalue at 0.561; 51 = 0.289
Pvalue > α ; Fail to Reject H0 and conclude that average marriage is not greater Tha or equal to 2500
D.)
H0 : μ = 4000
H0 : μ ≤ 4000
xbar = 1451 ; s = 1217 ; n = 52 ; α = 0.01
The test statistic :
T = (xbar - μ) ÷ (s/√(n))
T = (1451 - 4000) ÷ (1217/√52)
T = - 15.10
Pvalue from Test statistic : ; df = n - 1 = 52-1= 51
Pvalue at - 15.10; 51 = 0.000001
Pvalue < α ; Reject H0 and conclude that average divorce is less eqaul to 4000
A die is rolled nine times and the number of times that two shows on the upper face is counted. If this experiment is repeated many times, find the mean for the number of twos.
Answer:
[tex]E(x) = 1.5\\[/tex]
Step-by-step explanation:
Given
[tex]n = 9[/tex] -- number of rolls
Required
The mean of 2's
The distribution follows binomial distribution where:
[tex]X \to Binomial(n,p)[/tex]
In this case:
[tex]p= \frac{1}{6}[/tex] ---- the theoretical probability of rolling 2
So, the mean of 2's is calculated using:
[tex]E(x) = np[/tex]
[tex]E(x) = 9 * \frac{1}{6}[/tex]
[tex]E(x) = \frac{9}{6}[/tex]
Simplify
[tex]E(x) = \frac{3}{2}[/tex] or
[tex]E(x) = 1.5\\[/tex]
How many x-intercepts are in the quadratic equation y = 7x2 − 2x − 1
Answer:
There are 2 x intercepts
Which of the following is the result of the equation below after completing the square and factoring? x^2-4x+2=10
A. (x-2)^2=14
B. (x-2)^2=12
C. (x+2)^2=14
D. (x+2)^2=8
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Answer:
B. (x-2)^2=12
Step-by-step explanation:
The constant that completes the square is the square of half the coefficient of the x-term. That value is (-4/2)^2 = 4.
There is already a constant of 2 on the left side of the equal sign, so we need to add 2 to both sides to bring that constant value up to 4.
x^2 -4x +2 = 10 . . . . . . . given
x^2 -4x +2 +2 = 10 +2 . . . . complete the square (add 2 to both sides)
(x -2)^2 = 12 . . . . . . . . . write as a square
A five-question multiple-choice quiz has five choices for each answer. Use the random number table provided, with O's representing Incorrect answers
and 1's representing correct answers, to answer the following question:
What is the probability of correctly guessing at random exactly one correct answer? Round to the nearest whole number.
Answer:
Step-by-step explanation:
jnow colata
The function ()=5^3+3x−6 has inverse function . Find ′(138).
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Answer:
f⁻¹(138) = 3
Step-by-step explanation:
You want to find the value of x that makes the function have a value of 138:
f(x) = 5x^3 +3x -6
138 = 5x^3 +3x -6
0 = 5x^3 +3x -144
Descartes's rule of signs tells us this has one positive real solution. The rational root theorem gives us 30 possibilities. Rewriting the equation as ...
x^3 = (144 -3x)/5 = 28.8 -0.6x
suggests that the value of x is less than ∛28.8 ≈ 3.065. Trying x=3, we find that to be a solution.
(5x² +3)(x) -6 = 0 . . . . rewrite of the above equation
(5·3² +3)·3 -144 = (48)(3) -144 = 0 . . . . true
Then ...
f⁻¹(138) = 3
_____
The answer is found easily using a graphing calculator. The solution is the x-intercept of 138 -f(x) = 0.
Simplify. v80
A. 16v5
B. 5v4
C. 4v5
D. 20v4
Hi!
√80 = √(16 • 5) = √(4² • 5) = 4√5
1 red marble 4 blue marbles 3 green marbles probability of drawing 2 blue marbles
Answer:
3/14
Step-by-step explanation:
Assuming you draw one after the other without replacement, you have a 1/2 chance of drawing blue the first time, and after one is taken out, you have 7 left. In order to draw 2 blues you would have to have a blue the first time, so there would be 3 blue left. Multiplying the 2 probabilities gets 1/2*3/7= 3/14. Double check that though.
what the mining of althoe
[tex]y \geqslant 3[/tex]
The question isn't well stated ; If the question intends to ask the meaning of the inequality :
Answer:
Kindly check explanation
Step-by-step explanation:
Given the inequality : y ≥ 3
This inequality statement or expression means that :
y is true for all values beginning from 3 and beyond
That is values from 3 makes the expression a true statement.
Therefore values of y for which the inequality holds or is true are :
(3,....)
Read the following scenario, and then answer the question.
Juan assumes that the temperature of the hot tea cooling on his desk can be modeled with an exponential function like this one: T(t)=179(0.92)t. He bases his assumption on the following: The tea cools about 8% every minute. The tea's current temperature is around 179 degrees Fahrenheit.
Which explanation correctly addresses Juan's assumption?
He is incorrect. The tea will cool linearly since it cools at the same number of degrees every minute.
He is correct. The tea will cool exponentially since it cools at a percentage rate every minute.
He is incorrect. The tea will cool along the curve of a parabola since it cools at an increasing percentage rate every minute.
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Answer:
(b) He is correct. The tea will cool exponentially since it cools at a percentage rate every minute.
Step-by-step explanation:
Newton's Law of Cooling says the change in temperature is proportional to the temperature. This relation gives rise to an exponential function describing the temperature.
In this description, the temperature referred to is the difference between the temperature of the object and the temperature of the environment to/from which heat is being transferred.
Juan is only partially correct. The function is exponential, but the temperature that should be used in his equation is not the temperature of the tea, but the temperature difference between the tea and his desk.
__
The curve is not linear and not parabolic, excluding the other answer choices.
Which figure can be formed from the net?
pls answer fast for brainiest !
Answer:
It should be the top right one
(with 6ft as the height)
Step-by-step explanation:
Answer:
It must be the lower to the left choice.
Step-by-step explanation:
As you can see, the net we have is composed of only triangles.
So we should be choosing a figure with a triangular base.
Our answers are narrowed down into the top right and lower left choices because both figures have triangular bases.
The other person down there chose the top right choice and was incorrect, so the answer should be the lower to the left figure.
Also, its the lower left figure because look at the triangular base, it is an isosceles meaning that two sides have the same length.
If the net says that the long side measures 9 ft, then the other two sides should be the same length and shorter than 9 ft. So the answer is the lower left figure.
Hope this helps
With a.b.c=1 and a+b+c=1
Prove that:
Answer:
HOPE IT HELPS PLZ MARK ME BRAINLIEST
Step-by-step explanation:
abc=1
⟹c=1/ab
1/(1+a+1/b)+1/(1+b+1/c)+1/(1+c+1/a)
=1/(1+a+1/b)+1/(1+b+ab)+1/(1+1/ab+1/a)
=b/(1+b+ab)+1/(1+b+ab)+ab/(1+b+ab)
=1+b+ab/(1+b+ab)
=1
Identify the effect on the graph of replacing f(x) by A f(x)
Answer:
See explanation
Step-by-step explanation:
Required
Effect of replacing [tex]f(x)[/tex] with [tex]f(x - h)[/tex]
f(x) is represented as: (x,y)
While
f(x - h) is represented as (x - h, y)
Notice the difference in both is that, the x value in f(x - h) is reduced by a constant h while the y value remain unchanged.
This means that the graph of f(x) will shift horizontally (i.e. along the x-axis) to the left by h units
Hi I need help with fraction
1
_ x 10
8.
Answer:
The answer is 1 1/4 or 5/4
Step-by-step explanation:
1/8 · 10 = 10/8
10/8 when simplified is 5/4
Categorize the following logical fallacy.
John Bardeen's work at the Advanced Institute for Physics has progressed so slowly that even his colleagues call him a plodder. Hence, it is prudent at present not to take seriously his current theory relating how strings constitute the smallest of subatomic particles.
a. Circular reasoning
b. False dilemma
c. Appeal to consequence
d. Ad hominem
e. Correlation implies causation
Answer:
d. Ad hominem
Step-by-step explanation:
A fallacy can be defined as a mistaken or false belief that are based on illogical arguments or reasoning.
However, a lot of people might actually think it to be true but it isn't. There are various types of fallacy, these include;
I. Black or white.
II. Non sequitur.
III. Appeal to moderation.
IV. Bandwagon.
V. Appeal to authority.
VI. Straw man.
VII. Oversimplification or hasty generalization.
VIII. Appeal to ignorance.
IX. Appeal to pity.
X. Ad hominem.
Ad hominem can be defined as a type of fallacy in which the motive, character, or some other aspect of a person is attacked rather than his or her position.
This ultimately implies that, Ad hominem is typically based on prejudices, emotions, or feelings rather than appealing to reason, intellect or substance.
In this scenario, John Bardeen's research work at the Advanced Institute for Physics has progressed so slowly that even his colleagues call him a plodder. As a result, the speaker concluded that it's prudent at present not to take seriously his current theory on how strings constitute the smallest of subatomic particles. Thus, the logical fallacy described above is an ad hominem because John's slowness in his research work is bone of contention for the speaker rather than analyzing and concentrating on his theory about strings.
The point-slope form of the equation of a line that passes through points (8, 4) and (0, 2) is y -4 = %(x -8). What is
the slope-intercept form of the equation for this line?
O y = ÷x-12
O y= x-4
O y= =x+2
O y= =x +6
Answer:
y= x-4
Step-by-step explanation:
Many people consider their smart phone to be essential! Communication, news, Internet, entertainment, photos, and just keeping current are all conveniently possible with a smart phone. However, the battery better be charged or the phone is useless. Battery life of course depends on the frequency, duration, and type of use. One study involving heavy use of the phones showed the mean of the battery life to be 15.25 hours with a standard deviation of 2.2 hours. Then the battery needs to be recharged. Assume the battery life between charges is normally distributed.
Required:
a. Find the probability that with heavy use, the battery life exceeds 11 hours.
b. You are planning your recharging schedule so that the probability your phone will die is no more than 5%. After how many hours should you plan to recharge your phone?
Answer:
a) The probability that with heavy use, the battery life exceeds 11 hours is 0.4602.
b) Using the standard normal table, After 6.8 hours should you plan to recharge your phone.
Step-by-step explanation:
a) The probability that with heavy use, the battery life exceeds 11 hours:-
P(x > 11) = 1 - p( x< 11)
[tex]=1- p P[(x - \mu) / \sigma < (11 - 10.75) / 2.4]\\\\=1- P(z < 0.10)[/tex]
Using z table distribution,
= 1 - 0.5398
= 0.4602
b) Using the standard normal table,
[tex]P(Z < z) = 5%\\\\\\\\= P(Z < -1.645 ) = 0.05 \\z = -1.645[/tex]
Using the z-score formula,
[tex]x = z \times \sigma + \mu\\x = -1.645 * 2.4 + 10.75\\x = 6.8 hours.[/tex]
What can you say about the y-values of the two functions f(x) = 3x -3 and
g(x) = 7x2 -3?
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Answer:
the y-values of g(x) are limited to values of at least -3, those of f(x) are not limitedthe y-values are the same for two different x-valuesStep-by-step explanation:
You can say lots of things about the y-values of these functions. A couple of observations are listed above. In addition, we can say the y-values of g(x) will be greater than those of f(x) for x-values not equal or between the x-values where the y-values are the same.
Answer:
• g(x) has the smallest possible y-value.
• The minimum y value of g(x) is -3.
Step-by-step explanation:
Ap3x
Solve the simultaneous equations
6
x
+
2
y
=
12
5
x
+
2
y
=
8
Answer: x=4, y=-6
Step-by-step explanation:
Find the domain and range of the relation.
the answer is in the picture above
Ernest bought t T-shirts. The shirts came in 6 packages. Write an expression that shows how many T-shirts were in each package.
Type an asterisk ( * ) if you want to use a multiplication sign and a forward slash ( / ) if you want to use a division sign.
Answer:
t / 6 = # of shirts in each package.
Step-by-step explanation:
total amount of shirts / total packages = # of shirts in each package
1 cm = 5km scale ratio
Answer: Definition: Ratio of the size of the map to its subject: Scale ... so scale = 1 cm / 100,000 cm = 1/100,000. - Scale ... STEP 1: - 2 cm represents 5 km
Step-by-step explanation:
STEP 1: - 2 cm represents 5 km - (write in full)
- STEP 2: - 1 cm represents 2.5 km - (divide so left side = 1)
- STEP 3: - 1 cm represents 250,000 cm - (convert to same units)
- STEP 4: - scale is 1 : 250,000 - (express as a representative fraction)
identify the largest value in fraction 3/4, 1/2, 3/5
Answer:
1/2
Step-by-step explanation:
The largest value in fraction it is 1/2 because the fraction is small amount .while the 3/4 is least amount .and 3/5 is greatest amount fractions
The force F (in pounds) needed on a wrench handle to loosen a certain bolt varies inversely with the length L (in inches) of the handle. A force of 40 pounds is needed when the handle is 7 inches long. If a person needs 20 pounds of force to loosen the bolt, estimate the length of the wrench handle. Round answer to two decimal places if necessary.
in inches
Answer:
14 inches
Step-by-step explanation:
Since F is inversely proportional to L,
[tex]f = \frac{k}{l} \\ when \: f = 40 \: l \: = 7 \\ \frac{k}{7} = 40 \\ k = 280 \\ when \: f = 20 \\ 20 = \frac{280}{l} \\ l = 14[/tex]
The cost of 5 gallons of ice cream has a variance of 64 with a mean of 34 dollars during the summer. What is the probability that the sample mean would differ from the true mean by less than 1.1 dollars if a sample of 38 5-gallon pails is randomly selected
Answer:
0.5587 = 55.87% probability that the sample mean would differ from the true mean by less than 1.1 dollars.
Step-by-step explanation:
To solve this question, we need to understand the normal probability distribution and the central limit theorem.
Normal Probability Distribution:
Problems of normal distributions can be solved using the z-score formula.
In a set with mean [tex]\mu[/tex] and standard deviation [tex]\sigma[/tex], the z-score 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 p-value, we get the probability that the value of the measure is greater than X.
Central Limit Theorem
The Central Limit Theorem establishes that, for a normally distributed random variable X, with mean [tex]\mu[/tex] and standard deviation [tex]\sigma[/tex], the sampling distribution of the sample means with size n can be approximated to a normal distribution with mean [tex]\mu[/tex] and standard deviation [tex]s = \frac{\sigma}{\sqrt{n}}[/tex].
For a skewed variable, the Central Limit Theorem can also be applied, as long as n is at least 30.
The cost of 5 gallons of ice cream has a variance of 64 with a mean of 34 dollars during the summer.
This means that [tex]\sigma = \sqrt{64} = 8, \mu = 34[/tex]
Sample of 38
This means that [tex]n = 38, s = \frac{8}{\sqrt{38}}[/tex]
What is the probability that the sample mean would differ from the true mean by less than 1.1 dollars ?
P-value of Z when X = 34 + 1.1 = 35.1 subtracted by the p-value of Z when X = 34 - 1.1 = 32.9. So
X = 35.1
[tex]Z = \frac{X - \mu}{\sigma}[/tex]
By the Central Limit Theorem
[tex]Z = \frac{X - \mu}{s}[/tex]
[tex]Z = \frac{35.1 - 34}{\frac{8}{\sqrt{38}}}[/tex]
[tex]Z = 0.77[/tex]
[tex]Z = 0.77[/tex] has a p-value of 0.77935
X = 32.9
[tex]Z = \frac{X - \mu}{s}[/tex]
[tex]Z = \frac{32.9 - 34}{\frac{8}{\sqrt{38}}}[/tex]
[tex]Z = -0.77[/tex]
[tex]Z = -0.77[/tex] has a p-value of 0.22065
0.77935 - 0.22065 = 0.5587
0.5587 = 55.87% probability that the sample mean would differ from the true mean by less than 1.1 dollars.
Identify the type of sampling used (random, systematic, convenience, stratified, or cluster sampling) in the situation described below. A man is selected by a marketing company to participate in a paid focus group. The company says that the man was selected because his name is among the first 200 in the phone number listings. Which type of sampling did the marketing company use?
A. Systematic sampling
B. Cluster sampling
C. Random sampling
D. Stratified sampling
E. Convenience sampling
Answer: convenience sampling
Step-by-step explanation:
Convenience sampling is also referred to as opportunity sampling or accidental sampling and it occurs when a sample is selected from the population that is convenient and close to hand for the researcher. It's usually used during pilot testing.
Convenience sampling is such that the primary data source that are first available will be used for the research without any additional requirements being made.