There is enough grass to feed six cows for three days. How long would the same amount of grass feed nine cows
Answer:
2 days
Step-by-step explanation:
Lets say that in one day, one cow eats 1 block of grass. So, six cows in three days would eat 18 blocks of grass in total. So 18 blocks of grass is how much we have. that means nine cows would eat that much in 2 days.
Nine children are to be divided into an A team, a B team and a C team of 3 each. The A team will play in one league, the B team in another, the C team in a third league. How many different divisions are possible
Answer:
The answer is "840".
Step-by-step explanation:
Following are the number of ways in which selecting a team A by 9 children:
[tex]= ^{9_{C_{3}}\\\\\\[/tex]
[tex]=\frac{9!}{3! \times 6!} \\\\=\frac{9\times 8\times 7\times 6!}{3 \times 2\times 1\times 6!}\\\\=\frac{9\times 8\times 7}{3 \times 2\times 1}\\\\=\frac{3\times 4\times 7}{1}\\\\=\frac{84}{1}\\\\=84[/tex]
Following are the number of ways in which selecting a team B by remaining 6 children:
[tex]= ^{6}_{C_{3}}[/tex]
[tex]= \frac{6!}{(3! \times 3!)}\\\\= \frac{6!}{(3\times 2\times 1 \times 3!)}\\\\= \frac{6\times 5 \times 4 \times 3!}{(3\times 2\times 1 \times 3!)}\\\\= \frac{ 5 \times 4 \times 3!}{3!}\\\\= 5 \times 4 \\\\=20[/tex]
Following are the number of ways in which selecting a team C by remaining 3 children:
[tex]= ^{3}_{C_{3}}\\\\=\frac{3!}{3!}\\\\= 1[/tex]
Following are the number of ways in which making 3 teams by 9 children:
[tex]= \frac{(84 \times 20 \times 1)}{3!}\\\\= \frac{(84 \times 20 )}{6}\\\\= 14 \times 20\\\\= 280\\\\[/tex]
(Note: we've split by 3! Because it also is necessary to implement three teams between themselves)
Now 3 leagues have to be played. One is going to be run by each team.
That is the way it is
Different possible divisions
[tex]= 280 \times 3!\\\\= 280 \times (3 \times 2 \times 1)\\\\= 840[/tex]
a mean equal to 5 cm. A simple random sample of wrist breadths of 40 women has a mean of 5.07
cm. The population standard deviation is 0.33 cm. Find the value of the test statistic?
Answer:
The value of the test statistic is [tex]z = 1.34[/tex]
Step-by-step explanation:
The test statistic is:
[tex]z = \frac{X - \mu}{\frac{\sigma}{\sqrt{n}}}[/tex]
In which X is the sample mean, [tex]\mu[/tex] is the value tested at the null hypothesis, [tex]\sigma[/tex] is the standard deviation and n is the size of the sample.
Test if the mean is equal to 5:
This means that the null hypothesis is [tex]\mu = 5[/tex]
A simple random sample of wrist breadths of 40 women has a mean of 5.07 cm. The population standard deviation is 0.33 cm.
This means that [tex]n = 40, X = 5.07, \sigma = 0.33[/tex]
Find the value of the test statistic?
[tex]z = \frac{X - \mu}{\frac{\sigma}{\sqrt{n}}}[/tex]
[tex]z = \frac{5.07 - 5}{\frac{0.33}{\sqrt{40}}}[/tex]
[tex]z = 1.34[/tex]
The value of the test statistic is [tex]z = 1.34[/tex]
We want to know if money affects happiness. We surveyed 20 people one week before they were notified of winning a large publishers clearing house sweepstakes and then again one month after they recieved their prize. What test would we use to compare their previous scores with their current scores
Answer:
Dependent Samples t test
Step-by-step explanation:
The dependent samples t test also called the paired t test are employed in statistical analysis when sample measurement in a certain group is to be paired with the sample measurement on the other group. This is possible because the samples used in the two groups are usually the same. Hence, pairing the samples is feasible in this case. This is different from independent t test as the samples in the groups are entirely different and distinct. Hence, giving no chance to match the samples together. In the scenario described above, the same 20 people(samples) formed the same group of measurement.
HELP ASAP PLS Select the correct answer.
A light bulb's brightness is reduced when placed behind a screen. The amount of visible light produced by the light bulb decreases by 25% with
each additional layer that is added to the screen. With no screen, the light bulb produces 750 lumens. The lumen is a unit for measuring the total
quantity of visible light emitted by a source,
Select the correct equation that can be used to represent the lumens, L, after x screen layers are added.
Answer:
D. 750(0.75)ˣ
Step-by-step explanation:
Let the new brightness be L'. Since our initial brightness L₀ reduces by 25 %, we have that L' = L₀ - 25% of L₀
L' = L₀ - 0.25L₀
L' = 0.75L₀
Adding the second screen, the new intensity is L" = L' - 25 % of L'
L" = L' - 0.25 L'
L" = 0.75L'.
Since L' = 0.75L₀,
L" = 0.75L' = 0.75(0.75L₀) = 0.75²L₀
Adding the third screen, the new intensity is L"' = L'' - 25 % of L''
L'" = L" - 0.25 L"
L"' = 0.75L".
Since L" = 0.75L' = 0.75²L₀
L"' = 0.75L" = 0.75(0.75²L₀) = 0.75³L₀
So, we see a pattern here.
The intensity after x screens is L = (0.75)ˣL₀
Since L₀ = 750 lumens,
L = 750(0.75)ˣ
6. What are the coordinates of W? (0,t) W 0 (,0) Rhombus (0, -1) o (-r, o) (0,r). (t,0)
Answer:
B. (-r, 0)
Step-by-step explanation:
W is on the x axis, so the y coordinate is 0.
It is also r away from the origin, so the x coordinate is -r
Hope this helps!
In the following please select whether a hypothesis test or a confidence interval is most appropriate.
a. A business owner wants to know what proportion of sales occur online for their store.
b. A book publisher wants to know if more than 25% of customers buy an entire book series all at once instead of as individual books.
c. A professor wants to know the proportion of students who regularly show up to class.
d. A researcher is interested in seeing if less than 50% of Americans support the tariffs on Chinese goods.
Answer:
A. Confidence interval
B. Hypothesis test
C. Confidence interval
D. Hypothesis test
Step-by-step explanation:
A hypothesis a hypothesis test is done in statistics whereby the person carrying out the test, tests an assumption concerning a population interval.
Confidence interval can be gotten from the statistics of observed data it provides a given range of values for a parameter that is not known.
A.we use the confidence interval here
B. We use the hypothesis test
C. The confidence interval is the appropriate test
D. The hypothesis would be best
Can someone help me please..
Answer:
Quadratic formula
Step-by-step explanation:
The function is quadratic because it is a parabola. Exponential functions shoot either upwards or downwards rapidly, and it is clearly not linear due to it's curve. It also isn't piecewise because the function never stops or starts irregularly.
Which of the following is NOT true of a perpendicular bisect or?
Answer:
The forth option
It forms a right angle with the segment.
Determine the mean and variance of the random variable with the following probability mass function. f(x)=(216/43)(1/6)x, x=1,2,3 Round your answers to three decimal places (e.g. 98.765).
Mean:
E[X] = ∑ x f(x) = 1 × f (1) + 2 × f (2) + 3 × f (3) = 51/43 ≈ 1.186
Variance:
Recall that for a random variable X, its variance is defined as
Var[X] = E[(X - E[X])²] = E[X ²] - E[X]²
Now,
E[X ²] = ∑ x ² f(x) = 1² × f (1) + 2² × f (2) + 3² × f (3) = 69/43
Then
Var[X] = 69/43 - (51/43)² = 366/1849 ≈ 0.198
(each sum is taken over x in the set {1, 2, 3})
A full glass of water can hold 1/6 of a bottle.
How many glasses of water can be filled with 3 bottles of water
Algebraically show that each of the given combinations are equivalent to the given functions. f(x) – g() is
equivalent to m(x) given:
f(0)
= - 3x + 5; g(x)
- 5x – 7; m(x) = 2x + 12
f(x) – g(x) = (
=
Is f(x) – g(x) equivalent to m(x)? yes
Answer:
[tex]f(x) - g(x) = 2x + 12[/tex]
[tex]m(x) = f(x) - g(x)[/tex] --- True
Step-by-step explanation:
Given
[tex]f(x) = -3x + 5[/tex]
[tex]g(x) = -5x - 7[/tex]
[tex]m(x) = 2x + 12[/tex]
Solving (a): [tex]f(x) - g(x)[/tex]
From the given parameters, we have:
[tex]f(x) = -3x + 5[/tex]
[tex]g(x) = -5x - 7[/tex]
So:
[tex]f(x) - g(x)=-3x+5 + 5x + 7[/tex]
Collect like terms
[tex]f(x) - g(x) = 2x + 12[/tex]
Solving (b) m(x) = f(x) = g(x)?
In (a), we have:
[tex]f(x) - g(x) = 2x + 12[/tex]
And
[tex]m(x) = 2x + 12[/tex] --- given
By comparison:
[tex]m(x) = f(x) - g(x)[/tex]
giving brainiest Elinor solved this problem. Is her answer correct?
8.93 times 0.15 = 4465. 4465 + 8930 = 13.395
No, Elinor should have placed the decimal point between the 1 and the 3.
No, she should have placed the decimal point between the 3 and the 9.
No, she did not align the place values in the partial products correctly.
Yes. Elinor did not make an error. giving Branniest
Answer:
its a
Step-by-step explanation:
trust did test
two trains leave the station at the same time, one traveling due east, the other due west. After 46 minutes, they are 140 miles apart. if one trains speed is 20 mph more than the other trains, what are the speeds of the two trains?
Answer:
Train A speed = x + 20
Train B = x
We know the 46 minutes is 23/30 of an hour.
Use D = rt
Take it from it, hope its helped, have a great day!
PLEASE HELPP ITS AN EMERGENCY
Find the measure of angle A.
The expression x−y equals 0.7 if x and y have certain values. Evaluate the following expressions with the same values of x and y. What is 1/x-y.
PLEASE HELP FAST I NEED THIS DONE IN 30 MINUTES!!!
Answer:
10/7 or 1.428571429
Step-by-step explanation:
We know that x-y=0.7
So, now we have the equation 1÷0.7 or 1÷7/10
Meaning, we can multiply by the reciprocal,
And make this equation into 1×10/7= 10/7
Please help me in this question
Answer:
3/8
Step-by-step explanation:
the total number of possible results is 4×4=16.
out of these 16 only the results
1 2
1 3
1 4
2 2
2 3
3 2
are desired results. these are 6.
so the probability of a desired result is 6/16 = 3/8
For a confidence level of 88%, find the critical value for a normally distributed variable. The sample mean is normally distributed if the population standard deviation is known.
Answer:
z = ± 0.772193214
Step-by-step explanation:
Hence, the critical value for a [tex]88[/tex]% confidence level is [tex]z=1.56[/tex].
What is the standard deviation?
Standard deviation is the degree of dispersion or the scatter of the data points relative to its mean, in descriptive statistics.
It tells how the values are spread across the data sample and it is the measure of the variation of the data points from the mean.
Here given that,
For a confidence level of [tex]88[/tex]%, find the critical value for a normally distributed variable.
Let us assume that the standard normal distribution having a mean is [tex]0[/tex] and the standard deviation is [tex]1[/tex].
As the significance level is [tex]1[/tex] - confidence interval
Confidence interval is [tex]\frac{80}{100}=0.88[/tex]
i.e., [tex]1-0.88=0.12[/tex]
For the two sided confidence interval the confidence level is [tex]0.44[/tex].
Now, the standard normal probability table the critical value for the [tex]88[/tex]% confidence level is [tex]1.56[/tex].
Hence, the critical value for a [tex]88[/tex]% confidence level is [tex]z=1.56[/tex].
To know more about the standard deviation
https://brainly.com/question/13905583
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Which parabola opens upward?
y = 2x – 4x^2 – 5
y = 4 – 2x^2 –5x
y = 2 + 4x – 5x^2
y = –5x + 4x^2 + 2
Answer:
D) y = –5x + 4x^2 + 2
Step-by-step explanation:
You can tell by the first number being positive or negative. To check use Desmo graphing calculator and enter your equation for next time.
Of five letters (A, B, C, D, and E), two letters are to be selected at random. How many possible are possible
Answer:
10
Step-by-step explanation:
5C2 =5!
2! (3)!
=1 x 2 x 3 x 4 x 5
(1 x 2) (1 x 2 x 3)
=4 x 5
2
=20
2
5C2 = 10
Solve 7 pleaseeeeeeeeeeeeeeeee
Answer:
5040
Step-by-step explanation:
I assume you really mean 7!
you understand what "!" means ?
n! = n×(n-1)×(n-2)×(n-3)×...×3×2×1
so,
7! = 7×6×5×4×3×2×1
now all you need is a calculator.
7! = 5040
If (3x − 2)(3x + 2) = ax2 − b, what is the value of a?
(3x-2)(3x+ 2)
Multiply each term in one set of parentheses by the other terms:
3x x 3x =9x^2
3x x 2 = 6x
-2 x 3x = -6x
-2 x 2 = -4
Combine to get:
9x^2 + 6x - 6x -4
Combine like terms:
9x^2 - 4
The value of a would be 9.
[tex]\sf{\bold{\blue{\underline{\underline{Given}}}}}[/tex]
(3x − 2)(3x + 2) = ax2 − b⠀⠀⠀⠀[tex]\sf{\bold{\red{\underline{\underline{To\:Find}}}}}[/tex]
⠀what is the value of a?⠀⠀⠀[tex]\sf{\bold{\purple{\underline{\underline{Solution}}}}}[/tex]
At first we have to solve the value of (3x-2)(3x+2)
[tex]\sf{(3x-2)(3x+2) }[/tex] [tex]\sf{3x(3x+2)-2(3x+2) }[/tex] [tex]\sf{9x^{2}+6x-6x-4 }[/tex] [tex]\sf{9x^{2}-4 }[/tex]According to the question,
[tex]\sf{ (3x − 2)(3x + 2) = ax^{2} − b }[/tex] [tex]\sf{9x^{2}-4=ax^{2}-b }[/tex] [tex]\sf{9x^{2}=ax^{2}~and~-4=-b }[/tex] [tex]\sf{a=9~and~b=4 }[/tex]⠀⠀⠀
[tex]\sf{\bold{\green{\underline{\underline{Answer}}}}}[/tex]
Hence,
The value of a is 9
PLEASE HELP!!! Which number is a solution of the inequality x less-than negative 4? Use the number line to help answer the question. A number line going from negative 9 to positive 1.
Answer:
is it going to be 10.5
Step-by-step explanation:
I do not have any explanation
Answer: 0 (zero)
Step-by-step explanation:
Start Learning & start growing! edge2023
*DROPS THE MIC*
The endpoints of a line are (10, 4) and (-2, 8). Find the slope of
the line.
Aaron used ordinary electrical wire to connect the lights around the new factory. He ended up using 3 entire spools of wire, which totaled 1,380 feet. What is the number of feet of wire contained on one spool, written as a ratio? Type your ratio using a : between the numbers
Answer:
There are 460 feet of wire contained on one spool.
Step-by-step explanation:
Since Aaron used ordinary electrical wire to connect the lights around the new factory, and I have ended up using 3 entire spools of wire, which totaled 1,380 feet, to determine what is the number of feet of wire contained on one spool, written as a ratio, the following calculation must be performed:
1380/3 = X
460 = X
So there are 460 feet of wire contained on one spool.
rationalize the denominator of √3+√2\ 5+√2
Answer:
[tex]\frac{ 5 \sqrt3 \ + \ 5 \sqrt2 \ - \ \sqrt6 \ - \ 2}{23}[/tex]
Step-by-step explanation:
[tex]\frac{\sqrt3 \ + \ \sqrt2 }{5 \ + \ \sqrt2 } \\\\=\frac{\sqrt3 \ + \ \sqrt2 }{5 \ + \ \sqrt2 } \times \frac{5 \ - \ \sqrt2 }{5 \ - \ \sqrt2 } \\\\=\frac{( \sqrt3 \ + \ \sqrt2)(5 \ - \ \sqrt2)}{(5 \ + \ \sqrt2)( 5 \ - \ \sqrt 2 )}\\\\=\frac{( \sqrt3 \ + \ \sqrt2)(5 \ - \ \sqrt2)}{(5 \ + \ \sqrt2)( 5 \ - \ \sqrt 2 )}\\\\=\frac{5 \sqrt3 \ + \ 5\sqrt 2 \ - \ \sqrt{ 3\times 2 } \ - \ \sqrt{2 \times 2}}{(5)^2 \ - \ (\sqrt2)^2}\\\\= \frac{ 5 \sqrt3 \ + \ 5 \sqrt2 \ - \ \sqrt6 \ - \ 2}{25 - 2}\\\\[/tex]
[tex]= \frac{ 5 \sqrt3 \ + \ 5 \sqrt2 \ - \ \sqrt6 \ - \ 2}{23}[/tex]
Instructions: Drag and drop the correct name for each angle. Each angle has more than one name so be sure to identity all the correct names
Answer/Step-by-step explanation:
Recall: an angle can be named in three different ways:
i. Using one letter which is the vertex of the angle. i.e. if the vertex of the angle is A we can name the angle as <A.
ii. Using the number of the labelled angle. i.e. is the angle is labelled 2, we can name it <2
iii. Using the three letters of the angles with the vertex angle in the middle. i.e. if the three points that form an angle are A, B, C and the vertex is B, we can name the angle as <ABC.
✔️Let's name the each angle given according:
1. <G, <3, and <FGH
2. <D, <4, and <CDE
3. <S and <TSR (the number seems blur and difficult to read. Whatever number is used to label the angle is what you'd use in naming the angle)
Please hlep x^2+6x+1=0
Answer:
Substitute into the quadratic formula
-6 ± √32 / 2
= -3 ± √16
= 1 and -1 are the answer
Answer:
x = - 3 ± 2[tex]\sqrt{2}[/tex]
Step-by-step explanation:
Given
x² + 6x + 1 = 0 ( subtract 1 from both sides )
x² + 6x = - 1
Using the method of completing the square
add/ subtract ( half the coefficient of the x- term)² to both sides
x² + 2(3)x + 9 = - 1 + 9
(x + 3)² = 8 ( take the square root of both sides )
x + 3 = ± [tex]\sqrt{8}[/tex] = ± 2[tex]\sqrt{2}[/tex] ( subtract 3 from both sides )
x = - 3 ± 2[tex]\sqrt{2}[/tex]
Then
x = - 3 - 2[tex]\sqrt{2}[/tex] , x = - 3 + 2[tex]\sqrt{2}[/tex]
How many digit numbers with all ranging from to have at least of their digits equal. How many have exactly equal digits
Answer:
Step-by-step explanation:
Please can you re-write your question, the question is incomplete and difficult to understand.
Thanks.
A university found that 25% of its students withdraw without completing the introductory statistics course. Assume that 30 students registered for the course.Use Microsoft Excel whenever necessary and answer the following questions:Compute the probability that 2 or fewer will withdraw
Answer:
0.0106 = 1.06% probability that 2 or fewer will withdraw
Step-by-step explanation:
For each student, there are only two possible outcomes. Either they withdraw, or they do not. The probability of an student withdrawing is independent of any other student, 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.
25% of its students withdraw without completing the introductory statistics course.
This means that [tex]p = 0.25[/tex]
Assume that 30 students registered for the course.
This means that [tex]n = 30[/tex]
Compute the probability that 2 or fewer will withdraw:
This 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_{30,0}.(0.25)^{0}.(0.75)^{30} = 0.0002[/tex]
[tex]P(X = 1) = C_{30,1}.(0.25)^{1}.(0.75)^{29} = 0.0018[/tex]
[tex]P(X = 2) = C_{30,2}.(0.25)^{2}.(0.75)^{28} = 0.0086[/tex]
[tex]P(X \leq 2) = P(X = 0) + P(X = 1) + P(X = 2) = 0.0002 + 0.0018 + 0.0086 = 0.0106[/tex]
0.0106 = 1.06% probability that 2 or fewer will withdraw