Given:
E is the midpoint of AD and BC.
To prove:
[tex]\Delta AEC\cong DEB[/tex]
Proof:
Statement Reason
1. E is the midpoint of AD and BC 1. Given
2. [tex]AE\cong DE[/tex] 2. Definition of midpoint
3. [tex]CE\cong BE[/tex] 3. Definition of midpoint
4. [tex]\angle AEC\cong \angle DEB[/tex] 4. Vertically opposite angle
5. [tex]\triangle AEC\cong \triangle DEB[/tex] 5. SAS congruence postulate
Hence proved.
Laura makes a sound that 80.9 dB loud. Sarah makes a sound that is 3 time as intense. What is the loudness of Sarah's sound (in dB)
Answer:
242.7 dB
Step-by-step explanation:
what is the value of k
Answer:
(A)
Step-by-step explanation:
M=-2
therefore
x¹=3, y¹=-12, x²=6 y²=k
M=(y²-y¹)/(x²-x¹)
-2=(k+12)/(6-3)
-2×3=k+12
-6=k+12
k=-18
Using the order of operations, what is the last calculation that should be done to evaluate 4(8 - 6952 - 6+(-3)
4(8 - 6352 – 6 + (-3)
4(2)52 - 6+(-3)
4(2)(25) - 6+(-3)
200 - 6+(-3)
200 - (-2)
Answer:
200 + 2
Step-by-step explanation:
you know that two (2) negatives multiplying each other is = +
=200 +2
=202
I don't know how to do this. Please help
Answer:
63m³
Step-by-step explanation:
volume of a cylinder = πr²h
r = 2m, h = 5m
= 22/7 × 2² × 5
= 62.86m³
approx 63m³
Help me please and thank you
Step-by-step explanation:
jlejej
are u using chrome os
½ sejam berapa minit?
Answer:
1/2 jam 30 menit mungkin?
1/2 jam adalah 30 minit
1/2 × 60 = 30 mins
English translation
1/2 an hour is 30 minutes
1/2 × 60 = 30 mins
Answered by Gauthmath must click thanks and mark brainliest
b) An achievement test was administered to a class of 20,000 students. The mean score was 80 and the standard deviation was 11. If Lingard scored 72 in the test, how many students did better than him
Answer: 15328
Step-by-step explanation:
The following can be deduced from the information given:
N = 20000
μ = 80
σ = 11
P(X>72) = 1 - P (X<72)
= 1 - P(Z < 72-80/11)
= 1 - P(Z < -8/11)
= 1 - P(Z < 0.7272)
= 1 - 0.2336 = 0.7664
Therefore, the number of students that were better than Lingard n(X > 72) will be:
= 20000 × 0.7664
= 15328
A poll of 1,068 adult Americans reveals that 48% of the voters surveyed prefer the Democratic candidate for the presidency. At the 0.05 level of significance, test the claim that at least half of all voters prefer the Democrat.
a. Identify the null and alternative hypotheses.
b. Find the test statistic and P-value.
c. State the conclusion about the null hypothesis.
d. State the final conclusion that addresses the original claim.
Answer:
Step-by-step explanation:
H0 = .5 prefer Democratic candidate
Ha > .5 prefer Democratic candidate
p = .48
z = -1.285179129
0.9006 >= .05 thus we "FAIL TO REJECT THE NULL HYPOTHESES"
OMG!! I’m stuck on 4a) b) c)
Help please
Answer:
a) 750 cmb) 288 cmc) 2112 cmStep-by-step explanation:
Formula for getting the surface area of a rectangular prism: SA = 2 (WL + HL + HW)a) SA = 2 (WL + HL + HW) = 2(75) + 2(225) + 2(75) = 150 + 450 + 150 = 750 cm^2b) SA = 2 (WL + HL + HW)= 2(48) + 2(72) + 2(24)= 96 + 144 + 48=288 cm^2c) SA = 2 (WL + HL + HW)= 2(400) + 2(400) + 2(256)= 800 + 800 + 512= 2112 cm^2[tex]\tt{ \green{P} \orange{s} \red{y} \blue{x} \pink{c} \purple{h} \green{i} e}[/tex]
Answer:
Below in bold.
Step-by-step explanation:
(a) The surface area consists of the sum of the area of 3 sets of 2 congruent rectangles. The 2 rectangles are on opposite sides of the solid.
= 2(15*15) + 2(5*15) + 2(5&15)
= 450 + 150 + 150
= 750 unit^2.
(b). Similarly to the above:
Surface area = 2(12*6) + 2(4*12) + 2(4*6)
= 144 + 96 + 48
= 288 unit^2.
(c) Again:
Surface area = 2(25*16) + 2(25*16) + 2(16*16)
= 400 + 400 + 256
= 1056 unit^2.
Differentiate the following Functions
5x^2-2xy + 4y^3= 5
Answer:
[tex]\displaystyle y' = \frac{y - 5x}{x + 6y^2}[/tex]
General Formulas and Concepts:
Algebra I
Terms/CoefficientsFactoringCalculus
Differentiation
DerivativesDerivative NotationImplicit DifferentiationDerivative Property [Multiplied Constant]: [tex]\displaystyle \frac{d}{dx} [cf(x)] = c \cdot f'(x)[/tex]
Derivative Property [Addition/Subtraction]: [tex]\displaystyle \frac{d}{dx}[f(x) + g(x)] = \frac{d}{dx}[f(x)] + \frac{d}{dx}[g(x)][/tex]
Basic Power Rule:
f(x) = cxⁿf’(x) = c·nxⁿ⁻¹Derivative Rule [Product Rule]: [tex]\displaystyle \frac{d}{dx} [f(x)g(x)]=f'(x)g(x) + g'(x)f(x)[/tex]
Derivative Rule [Chain Rule]: [tex]\displaystyle \frac{d}{dx}[f(g(x))] =f'(g(x)) \cdot g'(x)[/tex]
Step-by-step explanation:
Step 1: Define
Identify
[tex]\displaystyle 5x^2 - 2xy + 4y^3 = 5[/tex]
Step 2: Differentiate
Implicit Differentiation: [tex]\displaystyle \frac{dy}{dx}[5x^2 - 2xy + 4y^3] = \frac{dy}{dx}[5][/tex]Rewrite [Derivative Property - Addition/Subtraction]: [tex]\displaystyle \frac{dy}{dx}[5x^2] - \frac{dy}{dx}[2xy] + \frac{dy}{dx}[4y^3] = \frac{dy}{dx}[5][/tex]Rewrite [Derivative Property - Multiplied Constant]: [tex]\displaystyle 5\frac{dy}{dx}[x^2] - 2\frac{dy}{dx}[xy] + 4\frac{dy}{dx}[y^3] = \frac{dy}{dx}[5][/tex]Basic Power Rule [Chain Rule]: [tex]\displaystyle 10x - 2\frac{dy}{dx}[xy] + 12y^2y' = 0[/tex]Product Rule: [tex]\displaystyle 10x - 2\bigg[ \frac{dy}{dx}[x]y + x\frac{dy}{dx}[y] \bigg] + 12y^2y' = 0[/tex]Basic Power Rule [Chain Rule]: [tex]\displaystyle 10x - 2\bigg[ y + xy' \bigg] + 12y^2y' = 0[/tex]Simplify: [tex]\displaystyle 10x - 2y + 2xy' + 12y^2y' = 0[/tex]Isolate y' terms: [tex]\displaystyle 2xy' + 12y^2y' = 2y - 10x[/tex]Factor: [tex]\displaystyle y'(2x + 12y^2) = 2y - 10x[/tex]Isolate y': [tex]\displaystyle y' = \frac{2y - 10x}{2x + 12y^2}[/tex]Factor: [tex]\displaystyle y' = \frac{2(y - 5x)}{2(x + 6y^2)}[/tex]Simplify: [tex]\displaystyle y' = \frac{y - 5x}{x + 6y^2}[/tex]Topic: AP Calculus AB/BC (Calculus I/I + II)
Unit: Differentiation
Book: College Calculus 10e
Cars arrive at a toll booth according to a Poisson process with mean 90 cars per hour. Suppose the attendant makes a phone call. How long, in seconds, can the attendant's phone call last if the probability is at least 0.1 that no cars arrive during the call
Answer:
92.12 seconds
Step-by-step explanation:
According to the poisson probability relation :
P(X =x) = (e^-λ * λ^x) / x!
For no calls to be reveived during the period, x = 0
P(X = 0) = (e^-λ * λ^0) / 0!
P(X = 0) = 0.1
0.1 = (e^-λ * λ^0) / 0!
0.1 = e^-λ
Take the In of both sides
In(0.1) = - λ
-2.303 = - λ
λ = 2.303
The length of call in second, l
l = λ / r ; r = arrival rate
r = 90 per hour ; this means ;
90 / 3600 = 0.025
l = 2.303 / 0.025
l = 92.12 seconds
An economist wants to estimate the mean per capita income (in thousands of dollars) for a major city in Texas. He believes that the mean income is $30.8, and the standard deviation is known to be $8.2. How large of a sample would be required in order to estimate the mean per capita income at the 95% level of confidence with an error of at most $0.39
Answer:
A sample of 1699 would be required.
Step-by-step explanation:
We have that to find our [tex]\alpha[/tex] level, that is the subtraction of 1 by the confidence interval divided by 2. So:
[tex]\alpha = \frac{1 - 0.95}{2} = 0.025[/tex]
Now, we have to find z in the Z-table as such z has a p-value of [tex]1 - \alpha[/tex].
That is z with a pvalue of [tex]1 - 0.025 = 0.975[/tex], so Z = 1.96.
Now, find the margin of error M as such
[tex]M = z\frac{\sigma}{\sqrt{n}}[/tex]
In which [tex]\sigma[/tex] is the standard deviation of the population and n is the size of the sample.
Standard deviation is known to be $8.2.
This means that [tex]\sigma = 8.2[/tex]
How large of a sample would be required in order to estimate the mean per capita income at the 95% level of confidence with an error of at most $0.39?
This is n for which M = 0.39. So
[tex]M = z\frac{\sigma}{\sqrt{n}}[/tex]
[tex]0.39 = 1.96\frac{8.2}{\sqrt{n}}[/tex]
[tex]0.39\sqrt{n} = 1.96*8.2[/tex]
[tex]\sqrt{n} = \frac{1.96*8.2}{0.39}[/tex]
[tex](\sqrt{n})^2 = (\frac{1.96*8.2}{0.39})^2[/tex]
[tex]n = 1698.3[/tex]
Rounding up:
A sample of 1699 would be required.
the incenter of a triangle is formed by the intersection of the of a triangle
Answer:
angle bisectors
Step-by-step explanation:
The incentre is where a triangle's three angle bisectors intersect ( an angle bisector is a ray that cuts an angle in half ). The incentre is the centre of a triangle drawn inside the triangle.
If the mean of a given dataset is
42 and the standard deviation is
4, where will a majority of the
data lie?
Answer:
A majority of the data will lie between 38 and 46.
Step-by-step explanation:
It can be said that a majority of the data of a distribution lies within 1 standard deviation of the mean.
In this question:
Mean of 42, standard deviation of 4.
42 - 4 = 38
42 + 4 = 46
A majority of the data will lie between 38 and 46.
Kevin's supervisor, Jill, has asked for an update on today's sales, Jill is pretty busy moving back and forth between different store locations. How can Kevin most effectively deliver an update to her ? a) Call with a quick update Ob ) Send a detailed text message c ) Book a one-hour meeting for tomorrow morning d) Send a detailed email
A study is conducted to compare the lengths of time required by men and women to assemble a certain product. Past experience indicates that the distribution of times for both men and women is approximately normal but the variance of the times for women is less than that for men. A random sample of times for 11 men and 14 women produced the following data:
Men:
n1= 11
s1= 6.1
Women:
n2= 14
s2= 5.3
Test the hypothesis that the variance for men is greater than for women. Use both p-value method and critical value approach.
Answer:
1.33 < 2.67 ; Fail to reject H0 at 0.05
Step-by-step explanation:
Given the data :
Men:
n1= 11
s1= 6.1
Women:
n2= 14
s2= 5.3
The hypothesis :
H0 : σ1² = σ2²
H1 : σ1² > σ2²
To calculate the test statistic ; we use th Ftest statistics ;
F statistic = Larger sample variance / Smaller sample variance
Fstatistic = s1² / s2² = 6.1² / 5.3² = 37.21/28.09 = 1.325
The F critical value at :
df numerator = n - 1 = 11 - 1 = 10
df denominator = n - 1 = 14 - 1 = 13
Using the F distribution table :
F critical = 2.671
Since
F statistic < F critical ; Fail to reject H0 at 0.05
We fail to reject the null hypothesis at significance level of H0 : s1² = s2²
For the men, we have:
n1= 11 s1= 6.1
For the women, we have:
n2= 14 s2= 5.3The null and the alternate hypotheses are:
Null hypothesis H0 : s1² = s2²Alternate hypothesis H1 : s1² > s2²
The numerator and the denominator degrees of freedom are calculated as:
[tex]\mathbf{df = n -1}[/tex]
So, we have:
[tex]\mathbf{df_1 = 11 -1}[/tex]
[tex]\mathbf{df_1 = 10}[/tex] ----- numerator
[tex]\mathbf{df_2 = 14 -1}[/tex]
[tex]\mathbf{df_2 = 13}[/tex] ----- denominator
The test statistic of the f test is:
[tex]\mathbf{t = \frac{s_1^2}{s_2^2}}[/tex]
So, we have:
[tex]\mathbf{t = \frac{6.1^2}{5.3^2}}[/tex]
[tex]\mathbf{t = \frac{37.21}{28.09}}[/tex]
[tex]\mathbf{t = 1.325}[/tex]
The critical values at [tex]\mathbf{t = 1.325}[/tex] and the degrees of freedom is:
[tex]\mathbf{F= 2.671}[/tex]
By comparison, 1.325 is less than 2.671.
Hence, we fail to reject the null hypothesis at H0 : s1² = s2²
Read more about hypothesis at:
https://brainly.com/question/23639322
a company has decreased the weight of its boxes of macaroni by 8 %. if the new weight of the box is 13.1ounces, what was the original weight of the box?
Answer:
실례합니다 ?
Step-by-step explanation:
이것이 무엇을 의미하는 질문입니까?
회사는 마카로니 상자의 무게를 8% 줄였습니다. 상자의 새 무게가 13.1온스인 경우 상자의 원래 무게는 얼마였습니까? 오른쪽 ?
Answer:
x*0.92 = 13.1
x = 14.24
Step-by-step explanation:
Classify the following data. Indicate whether the data is qualitative or quantitative, indicate whether the data is discrete, continuous, or neither, and indicate the level of measurement for the data.
A supervisor must give a summary evaluation rating from among the choices given below:
1) Poor
2) Fair
3) Good
4) Very good
5) Excellent
a. Are these data qualitative or quantitative?
b. Are these data discrete or continuous?
c. What is the highest level of measurement the data possesses?
Answer:
Qualitative data
Neither discrete or continous
Ordinal
Step-by-step explanation:
Qualitative data simply refers to Non-numeric measure, they make use of data labels which are expressed in words rather than figures or numbers.
For a data to be either discrete or continous, then it has to be numeric, since the data is qualitative and non- numeric, then it is neither continous or discrete.
This is an ordinal scale representation of data as data are ordered or ranked in terms of performance, however, there is no measure of difference between each rank or order. The highest level of performance in the scale is Excellent.
I NEED HELP PLEASE!!
Answer:
70
Step-by-step explanation:
70 because as the number of trials increase, the actual ratio of outcomes will converge on the expected ratio.
Dean Halverson recently read that full-time college students study 20 hours each week. She decides to do a study at her university to see if there is evidence that students study an average of more than 20 hours each week. A random sample of 35 students were asked to keep a diary of their activities over a period of several weeks. It was found that the average number of hours that the 35 students studied each week was 21.1 hours. The sample standard deviation of 4.3 hours.
Find the p-value.
The p-value should be rounded to 4-decimal places.
Answer:
0.0698
Step-by-step explanation:
Given :
Population mean, μ = 20
Sample mean, xbar = 21.1
Sample standard deviation, s = 4.3
Sample size, n = 35
The hypothesis :
H0 : μ = 20
H0 : μ > 20
The test statistic :
(xbar - μ) ÷ (s/√(n))
T = (21.1 - 20) ÷ (4.3/√(35))
T = 1.1 ÷ 0.7268326
Test statistic = 1.513
Using the Pvalue calculator :
df = n - 1 = 35 - 1 = 34
Pvalue(1.513, 34) = 0.06976
Pvalue = 0.0698 (4 decimal places)
The p-value is 0.0698 if rounded to 4-decimal places.
It is given that students study an average of more than 20 hours each week and the random sample of 35 students was asked to keep a diary of their activities over a period of several weeks.
The average number of hours that the 35 students was 21.1 hours.
The sample standard deviation is 4.3 hours.
It is required to find the p-value.
What is the standard deviation?It is defined as the measure of data dispersement, It gives an idea about how much is the data spread out.
We can test the hypothesis using the Z test, the formula for the Z-test is given below:
[tex]\rm Z= \frac{(x-u)}{\frac{S}{\sqrt{n} } }[/tex]
Where x is the sample mean
u is the population mean
s is the standard deviation
n is the sample size.
The hypothesis are: H0 : μ = 20 V/s H1 : μ > 20
We have x = 21.1
u = 20
s = 4.3
n = 35
Putting these values in the above formula, we get:
[tex]\rm Z= \frac{(21.1-20)}{\frac{4.3}{\sqrt{35} } }\\\\\rm Z= \frac{(1.1)}{\frac{4.3}{\sqrt{35} } }\\\\[/tex]
Z = 1.513
difference or df = n -1 ⇒ 35-1 ⇒ 34
P-value at (1.513, 34) = 0.06976 (From the p-value calculator)
P-value = 0.0698 (Rounded to 4-decimal places)
Thus, the p-value is 0.0698 if rounded to 4-decimal places.
Learn more about the standard deviation here:
brainly.com/question/12402189
Plz this is due today help me explain the answer
Answer:
177.3 feet
This is a classic find the vertex of a parabola question.
if this was a calculus class the solution would be to take the derivative and set it equal to zero... -32t+ 105 = 0
BUT i assume that you are not in a calculus class..
so we try plan "B" the highest (or lowest) point of parabola is it's vertex
the vertex formula is [-b/2a,f(-b/2a)]
in your problem a = -16, b=105, c= 5
so the "X" (TIME) is located at -(105)/(2*-16) = 3.28
plug in 3.28 into -16(3.28)^2 + 105(3.28) + 5 = 177.27
and you will get
Step-by-step explanation:
Y<3/2•x-4
Match the equation to a graph.
Answer:
Last option
Step-by-step explanation:
The slope 3/2 determines the line (although you can plot points to find (0,-4) and (4,2), connecting them, you'll get the equation of the line, and the area it covers will be to the right side, putting x = 0, y<-4, which is below the line, that's how you determine it.
Answered by GAUTHMATH
Urgent need the answers plz help.
Answer:
(a) [tex]P" = (-4,-3)[/tex]
(b) [tex](x,y) \to (4,-8)[/tex]
Step-by-step explanation:
Given
[tex]P = (4,3)[/tex]
Solving (a): Reflect across x and y-axis.
Reflection across x-axis has the following rules
[tex](x,y) \to (x,-y)[/tex]
So, we have:
[tex]P' = (4,-3)[/tex]
Reflection across y-axis has the following rules
[tex](x,y) \to (-x,y)[/tex]
So, we have:
[tex]P" = (-4,-3)[/tex]
Hence, the new point is: (-4,-3)
Solving (b): Rx . Do,2 (2,4)
[tex]R_x \to[/tex] reflect across the x-axis
Reflection across x-axis has the following rules
[tex](x,y) \to (x,-y)[/tex]
So, we have:
[tex](2,4) = (2,-4)[/tex] ---- when P is reflected across the x-axis
[tex]D_{o,2} \to[/tex] dilate by a scale factor of 2
The rule is:
[tex](x,y) \to 2 * (x,y)[/tex]
So, we have
[tex](x,y) \to 2 * (2,-4)[/tex]
Open bracket
[tex](x,y) \to (4,-8)[/tex]
(-4/9)*3×(-27/20)*4=
(-4/9)*3×(-27/20)*4= 7.2
Step-by-step explanation:
here's the answer to your question
Which fraction is greater than the fraction represented by the model?
HURRY PLS IM BEING TIMED!!!!
Answer:
7/16
Step-by-step explanation:
7/16>3/8
It would be 7/16 because 3/8 is what is being shown. If you make them both have a common denominator then it would be 6/16.
prove:
sin²A-cos²B=sin²B-cos²A
Step-by-step explanation:
thwashm m GB DC GM 3hka it g feeds ygzdkzyzuzjz indin, mi, hn zbe
Answer:
Solution given:
L.H.S
sin²A-cos²B
we havesin²A=1-cos²A and Cos²B=1-sin²B
nowreplacing value
1-cos²A-(1-sin²B)
open bracket1-cos²A-1+sin²B
keep together like terms1-1+sin²B-Cos²A
=sin²B-Cos²A
R.H.S
proved.A tourist from Britain wants to exchange her British pounds for US dollar. She has 25 British pounds. How many US dollars would she get in exchange for her British pound if 1 British pound can be exchanged for 1.53 US dollars?
Answer:
$38.25 US dollars.
Step-by-step explanation:
25 / 1 = 25
To find the number of US dollars that can be exchanged for 25 British pounds, multiply 1.53 by 25 to get $38.25 US dollars.
Hope this helps!
if there is something wrong, just let me know.
(x+7)(x-6) Find the product.ddddddddddddd
Answer:
x^2 + x - 42
Step-by-step explanation:
use the distributive property:
(x+7)(x-6) = x^2 + x - 42
Answer: x^2 + x - 42
Step-by-step explanation:
solve for x
8x2-5=11
Answer:
1
Explainion show in picture above
Answer:
x=6
Step-by-step explanation:
It should be 8+x+2-5=11
Find the standard deviation for the following group of data items.
9, 11, 11, 16
The standard deviation for the given data items is 2.6
The standard deviation of the given data items can be calculated by taking the square root of the variance.
Variance is a measure of variability and it is calculated by taking the average of squared deviations from the mean.
Hence, we will first determine the mean of the given data items.
Mean is simply the average of the numbers.
Therefore mean of the given data items is
[tex]Mean = \frac{9+11+11+16}{4}[/tex]
[tex]Mean = \frac{47}{4}[/tex]
Mean = 11.75
Now, for the variance of the data
[tex]Variance = \frac{(9-11.75)^{2}+(11-11.75)^{2}+(11-11.75)^{2}+(16-11.75)^{2} }{4}[/tex]
[tex]Variance = \frac{(-2.75)^{2}+(-0.75)^{2}+(-0.75)^{2}+(4.25)^{2} }{4}[/tex]
[tex]Variance = \frac{7.5625+0.5625+0.5625+18.0625}{4}[/tex]
[tex]Variance = \frac{26.75}{4}\\[/tex]
∴ Variance = 6.6875
But,
Standard deviation [tex]= \sqrt{Varinace}[/tex]
∴Standard deviation [tex]=\sqrt{6.6875}[/tex]
Standard deviation = 2.586
Standard deviation ≅ 2.6
Hence, the standard deviation for the given data items is 2.6
Learn more on standard deviation here: https://brainly.com/question/18562832