Answer:
Test Statistic = 10
Critical Value = 9.488
Step-by-step explanation:
Given :
Grade A _ B _ C _ D _ F
_____14 _ 18 _32_ 20_16
H0 : distribution of grade is uniform
H1 : Distribution of grade is not uniform
Using the Chisquare statistic :
χ² = (observed - Expected)² / Expected
The expected value :
(14+18+32+20+16) / 5 = 20
χ² = (14-20)^2 / 20 + (18-20)^2 / 20 + (32-20)^2 / 20 + (20-20)^2 / 20 + (16-20)^2 / 20
χ² statistic = 10
The χ² critical at df = (n - 1) = 5 - 1 = 4
χ² Critical(10, 4) = 9.488
Jill records the temperature outside every hour for 4 hours. She finds that the temperature dropped by the same amount each hour. After 4 hours, she finds that the temperature dropped a total of 20∘F. She writes this number sentence.
(−20)÷4=−5
What does the number sentence mean?
The total drop in temperature, −20∘F, divided by 4 hours equals −5∘F per hour. The temperature dropped 5∘F each hour.
The total number of drops, 20, divided by 4 hours equals 5 times per hour. The temperature dropped 5 times per hour.
The total number of hours, 20, divided by 4∘F equals 5 hours. The temperature dropped once every 5 hours.
The total drop in temperature, −20∘F, divided by 4∘F in the first hour, equals −5 drops. The temperature dropped 5 times.
Answer:
It is the first one, The total drop in temperature, −20∘F, divided by 4 hours equals −5∘F per hour. The temperature dropped 5∘F each hour.
Step-by-step explanation:
Find the transpose of AB
Answer:
see above is the answer handwriting is bad sorry for that
Stuck on this one!!
Shelly believes the honor roll students at her school have an unfair advantage in being assigned to the math class they request. She asked 500 students at her school the following questions: "Are you on the honor roll?" and "Did you get the math class you requested?" The results are shown in the table below:
Honor roll Not on honor roll Total
Received math class requested 125 215 340
Did not get math class requested 80 80 160
Total 205 295 500
Help Shelly determine if all students at her school have an equal opportunity to get into the math class they requested. Show your work, and explain your process for determining the fairness of the class assignment process.
Answer: No, there isn't equal opportunity
======================================================
Explanation:
Let's define the two events
A = person is on the honor rollB = person got the math class they requestedFrom the table, we see that
P(B) = 340/500 = 0.68
meaning that there's a 68% chance of picking someone who got the class they wanted (i.e. 68% of the people got the class they wanted)
------------
Now let's assume that the person is on the honor roll. This means we only focus on the "honor roll" column. There are 125 people here that got the class they wanted out of 205 honor roll students total.
So,
P(B given A) = 125/205 = 0.609756
which rounds to 0.61
This says that if a person is on the honor roll, then they have roughly a 61% chance of getting the class they want.
The chances have gone down from 68% to 61% roughly.
------------
It appears that being on the honor roll does affect your chances of getting into the class you want.
Therefore, all students do not have the same equal opportunity.
We would need to have P(B) and P(A given B) to be the same exact value for true equal opportunity to happen.
All students do not have equal opportunity.
From the table, we have the following parameters:
205 people are on honor roll call340 people got the math class requested500 people were surveyedThe above means that:
The probability that a person is on honor roll call is:
p1 = 205/500
p1 = 0.41
The probability that a person got the math class requested
p2 = 340/500
p2 = 0.68
Both probabilities are not equal.
Hence, it is true that all students do not have equal opportunity.
Read more about probability at:
https://brainly.com/question/25870256
which function is positive for the entire interval (-3,-2)
Answer:
There can be several such functions; however, the basic condition that needs to be met for a function to be positive for the interval [–3, –2] is that it should be multiplied by (-1) Hence, one such function that is positive for the entire interval is f(x) = -x
Step-by-step explanation:
Which expression is equivalent to (4x^(3)y^(5))(3x^(5)y)^(2)
Answer:
[tex](4x^3y^5)(3x^5y)^2 = 36*x^{13}y^7[/tex]
Step-by-step explanation:
Given
[tex](4x^3y^5)(3x^5y)^2[/tex]
Required
The equivalent expression
We have:
[tex](4x^3y^5)(3x^5y)^2[/tex]
Expand
[tex](4x^3y^5)(3x^5y)^2 = 4x^3y^5*9x^{10}y^2[/tex]
Further expand
[tex](4x^3y^5)(3x^5y)^2 = 4*9*x^3*x^{10}y^5*y^2[/tex]
Apply laws of indices
[tex](4x^3y^5)(3x^5y)^2 = 36*x^{13}y^7[/tex]
Let f(x)=5-4x. Find f(3)
Answer:
-7
Step-by-step explanation:
f(x) = 5 - 4x
f(3) = 5 - 4(3) (since x = 3)
f(3) = 5 - 12
f(3) = -7
Pls if anyone knows the answer that will be greatly appreciated :)
Answer:
Volume 1=27m³
Volume 2=13m³
Volume 3= 23m³
Which expression is equivalent to 15 n=10 (n+3/n)?
Answer:
±√6
Step-by-step explanation:
[tex]15n=10(n+\frac{3}{n} )[/tex] is your expression first muiltiply out the 10 to get 15n= 10n+10 3/n next subtract 10 n from both sides to get 5n=10+3/n multiply both sides by n to get 5n^2=13 combine both sides and use the quadratic equation to solve to get your solution of ±√6
If lan does a job in 132 hours and with the help of Danielle they can do it together in 44 hours, how long
would it take Danielle to do it alone
Answer:
88 hours
Step-by-step explanation:
Ian = 132
Daniel + Ian = 44
Daniel = Ian - 44
= 132-44 = 88 hours
Which expression is equivalent to
128xy
5 ? Assume x > 0 and y> 0.
2xy5
Moto
8
yax
8
BV
y
8.VY
X
Answer:
[tex]\sqrt{128x^8y^3} = 8 x^4 y \sqrt{2y}[/tex]
Step-by-step explanation:
Given
[tex]\sqrt{128x^8y^3}[/tex] --- the complete expression
Required
The equivalent expression
We have:
[tex]\sqrt{128x^8y^3}[/tex]
Expand
[tex]\sqrt{128x^8y^3} = \sqrt{128* x^8 * y^3}[/tex]
Further expand
[tex]\sqrt{128x^8y^3} = \sqrt{64 * 2* x^8 * y^2 * y}[/tex]
Rewrite as:
[tex]\sqrt{128x^8y^3} = \sqrt{64 * x^8 * y^2* 2 * y}[/tex]
Split
[tex]\sqrt{128x^8y^3} = \sqrt{64 * x^8 * y^2} * \sqrt{2 * y}[/tex]
Express as:
[tex]\sqrt{128x^8y^3} = (64 * x^8 * y^2)^\frac{1}{2} * \sqrt{2y}[/tex]
Remove bracket
[tex]\sqrt{128x^8y^3} = (64)^\frac{1}{2} * (x^8)^\frac{1}{2} * (y^2)^\frac{1}{2} * \sqrt{2y}[/tex]
[tex]\sqrt{128x^8y^3} = 8 * x^\frac{8}{2} * y^\frac{2}{2} * \sqrt{2y}[/tex]
[tex]\sqrt{128x^8y^3} = 8 * x^4 * y * \sqrt{2y}[/tex]
[tex]\sqrt{128x^8y^3} = 8 x^4 y \sqrt{2y}[/tex]
I need you guy’s help answer thanks so much
Answer:
B. 7i
Step-by-step explanation:
first we need to find the root of the expression
[tex]\sqrt{-49} = \sqrt{49} *\sqrt{-1} \\ \\ \sqrt{49} = 7\\\\and\\\\ \sqrt{-1} = i[/tex]
so the answer is B. 7i
Hi friends,
Please assist with my question below.
In a right angle triangle, an angle of 30 degrees has an adjacent side which measures 17 cm. what is the length of its hypotenuse?
Answer : 19.6cm
I hope this helps you! Have a good day!
A 90% confidence interval is (35 45). What is the margin of error?
A. 5
B.4.5
C.9
D.10
Answer:
option A 5
I hope it's correct
.....
A researcher is interested in whether there is a significant difference between the mean age of marriage across three racial groups. Using the data provided below, conduct an F-test to determine whether you believe there is an association between race and average age at marriage.
Race N Mean
Black 113 25.39
White 904 22.99
Other 144 23.87
All Groups 1,161 23.33
Answer:
The P-value is < significance value ( 0.05 ) hence we reject the Null hypothesis ( i.e. There is an association between the race and average age at marriage )
Step-by-step explanation:
Conducting an F-test to determine association between race and average age at marriage
step 1 : State the hypothesis
H0 : ц1 = ц2 = ц3
Ha : ц1 ≠ ц2 ≠ ц3
step 2 : determine the mean square between
Given mean value of all groups = 23.33
SS btw = 113*(25.39 - 23.33)² + 904*(22.99 - 23.33)² + 144*(23.89 - 23.33)^2 = 113(4.2436) + 904(0.1156) + 144(0.3136)
= 629.1876
hence: df btw = 3 - 1 = 2
df total = 1161 - 1 = 1160
df within = 1160 - 2 = 1158
SS within = 36.87*1158 = 42695.46
Therefore the MS between = 629.19 / 2 = 314.60
The F-ratio = 314.59 / 36.87 = 8.53
using the values for Btw the P-value = 0.00021
The P-value is < significance value ( 0.05 ) hence we reject the Null hypothesis ( i.e. There is an association between the race and average age at marriage )
20 POINTS! The answer is x=4 and x= -5, how should I word it, saying how he is wrong?
Answer:
The student took the numbers for the factors 5, -4 for the zeros instead of solving the equation
The zeros are -5, 4
Step-by-step explanation:
x^2 +x - 20=0
What 2 number multiply to -20 and add to 1
5*-4 = -20
5+-4 = 1
(x+5)(x-4) =0
Using the zero product property
x+5 = 0 x-4 =0
x=-5 x=4
Answer:
Solution given:
equation is:
x²+x-20=0
doing middle term factorisation
note:we need to get 1 while subtracting factor of the product of constant and coefficient of x².
20*1=20=2*5*2*1
we get 1 while subtracting 5-2*2=5-4
now substitute value 5-4 at coefficient of x
we get
x²+(5-4)x-20=0
now
distribute
x²+5x-4x-20=0
taking common from each two term
x(x+5)-4(x+5)=0
again taking common (x+5) and keeping remaining at another bracket
(x+5)(x-4)=0
either
x+5=0
x=-5
or
x-4=0
x=4
Error is:
x= 4 not -4
x=-5 not 5.
Which expression is equivalent to 6x3 + 3y2 – 5x3 + 2y2?
Answer:
The answer is c because6X^3 minus 5X^3 is just X^3 and 3Y^2 plus 2Y^2 is 5Y^2.
Let h(x)=20e^kx where k ɛ R (Picture attached. Thank you so much!)
Answer:
A)
[tex]k=0[/tex]
B)
[tex]\displaystyle \begin{aligned} 2k + 1& = 2\ln 20 + 1 \\ &\approx 2.3863\end{aligned}[/tex]
C)
[tex]\displaystyle \begin{aligned} k - 3&= \ln \frac{1}{2} - 3 \\ &\approx-3.6931 \end{aligned}[/tex]
Step-by-step explanation:
We are given the function:
[tex]\displaystyle h(x) = 20e^{kx} \text{ where } k \in \mathbb{R}[/tex]
A)
Given that h(1) = 20, we want to find k.
h(1) = 20 means that h(x) = 20 when x = 1. Substitute:
[tex]\displaystyle (20) = 20e^{k(1)}[/tex]
Simplify:
[tex]1= e^k[/tex]
Anything raised to zero (except for zero) is one. Therefore:
[tex]k=0[/tex]
B)
Given that h(1) = 40, we want to find 2k + 1.
Likewise, this means that h(x) = 40 when x = 1. Substitute:
[tex]\displaystyle (40) = 20e^{k(1)}[/tex]
Simplify:
[tex]\displaystyle 2 = e^{k}[/tex]
We can take the natural log of both sides:
[tex]\displaystyle \ln 2 = \underbrace{k\ln e}_{\ln a^b = b\ln a}[/tex]
By definition, ln(e) = 1. Hence:
[tex]\displaystyle k = \ln 2[/tex]
Therefore:
[tex]2k+1 = 2\ln 2+ 1 \approx 2.3863[/tex]
C)
Given that h(1) = 10, we want to find k - 3.
Again, this meas that h(x) = 10 when x = 1. Substitute:
[tex]\displaystyle (10) = 20e^{k(1)}[/tex]
Simplfy:
[tex]\displaystyle \frac{1}{2} = e^k[/tex]
Take the natural log of both sides:
[tex]\displaystyle \ln \frac{1}{2} = k\ln e[/tex]
Therefore:
[tex]\displaystyle k = \ln \frac{1}{2}[/tex]
Therefore:
[tex]\displaystyle k - 3 = \ln\frac{1}{2} - 3\approx-3.6931[/tex]
The volume of the cylinder is V=1/3r^2h, where r is the radius and h is the height. if the radius of a cylinder is 3 inches and the height is 8 inches, which answer below best estimates it’s volume?
Answer:
75 inches
Step-by-step explanation:
with this we use change of subject
V=1/3
Pie=3.14
radius =3
height =8
so therefore
V=1/3 ×3.14×3×3×8
V=75.36
♥️♥️♥️♥️♥️♥️♥️♥️♥️ help me
9514 1404 393
Answer:
AC = 2.0 mm = 41.3 kgStep-by-step explanation:
The sum of torques about the pivot point is zero when the system is in equilibrium. That means the total of clockwise torques is equal to the total of counterclockwise torques. For this purpose, torque can be modeled by the product of mass and its distance from the pivot. The uniform beam can be modeled as a point mass at its center.
__
a) Let E represent the location of the center of mass of the beam. So, AE = 1.5 m. Then the distance from C to E is AC-AE = AC -1.5 and the CCW torque due to the beam's mass is (16 kg)(AC -1.5 m).
The distance from B to C is 3 m - AC, so the CW torque due to the particle at B is (7 kg)(3 -AC m)
These are equal, so we have ...
16(AC -1.5) = 7(3 -AC)
16AC -24 = 21 -7AC . . . . . eliminate parentheses
23AC = 45 . . . . . . . . . . . add 7AC+24
AC = 45/23 ≈ 1.957 . . divide by the coefficient of AC
AC ≈ 2.0 meters . . . . rounded to 1 dp
__
b) The torques in this scenario are ...
M(0.7) = 16(0.8) +7(2.3) . . . . . . AD = 0.7 m, DE = 0.8 m, DB = 2.3 m
M = 28.9/0.7 ≈ 41.286 . . . . simplify, divide by the coefficient of M
M = 41.3 kg . . . . rounded to 1 dp
_____
Additional comment
Torque is actually the product of force and distance from the pivot. Here, the forces are all downward, and due to the acceleration of gravity. The gravitational constant multiplies each mass, so there is no harm in dividing the equation by that constant, leaving the sum of products of mass and distance.
The data show the traveler spend- ing in billions of dollars for a recent year for a sample of the states. Find the range, variance, and standard deviation for the data.
20.1 33.5 21.7 58.4 23.2 110.8 30.9
24.0 74.8 60.0
Solution :
Given data :
20.1 33.5 21.7 58.4 23.2 110.8 30.9
24.0 74.8 60.0
n = 10
Range : Arranging from lowest to highest.
20.1, 21.7, 23.2, 24.0, 30.9, 33.5, 58.4, 60.0, 74.8, 110.8
Range = low highest value - lowest value
= 110.8 - 20.1
= 90.7
Mean = [tex]$\frac{\sum x}{n}$[/tex]
[tex]$=\frac{20.1+21.7+23.2+24.0+30.9+33.5+58.4+60.0+74.8+110.8}{10}$[/tex]
[tex]$=\frac{457.4}{10}$[/tex]
[tex]$=45.74$[/tex]
Sample standard deviation :
[tex]$S=\sqrt{\frac{1}{n-1}\sum(x-\mu)^2}$[/tex]
[tex]$S=\sqrt{\frac{1}{10-1}(20.1-45.74)^2+(21.7-45.74)^2+(23.2-45.74)^2+(24.0-45.74)^2+(30.9-45)^2}$[/tex]
[tex]\sqrt{(33.5-45.74)^2+(58.4-45.74)^2+(60.0-45.74)^2+(74.8-45.74)^2+(110.8-45.74)^2}[/tex]
[tex]$S=\sqrt{\frac{1}{9}(657.4+577.9+508.0+472.6+220.2+149.8+160.2+203.3+844.4+4232.8)}$[/tex][tex]$S=\sqrt{\frac{1}{9}(8026.96)}$[/tex]
[tex]$S=\sqrt{891.88}$[/tex]
S = 29.8644
Variance = [tex]S^2[/tex]
[tex]=(29.8644)^2[/tex]
= 891.8823
What is the remainder when x2+ 3 is divided by x - 1?
Answer:
Step-by-step explan
A 500-kg concrete block 95 cm longcm wide and cm high. It can exert three different pressures on a horizontal surface depending on which faceit rests on the highest pressure is
Pressure is force per unit area. If the block is sitting at rest on the surface, it applies a pressure of mg/A, where mg is the block's weight and A is the area of the face that makes contact with the surface.
The smaller the value of A, the larger the pressure. So the highest pressure the block can exert is achieved when it's resting on the face with the smallest dimensions.
If the block is a cube with side length 95 cm, then the pressure exerted by each face is the same.
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
Heather, a sociology major is interested in studying mass media topics. She is particularly interested in the percentage of mass media topics that relate to entertainment. Based on previous research, 72% of mass media topics relate to entertainment. She suspects this percent is different. During the process of hypothesis testing, she calculates a probability using the test statistic. What is the probability associated with the test statistic called
Answer:
Pvalue
Step-by-step explanation:
The Pvalue measure which takes up a value in the range 0 - 1 is a statistical measure used on hypothesis testing to measure the likelihood of obtaining result atleast as extreme as the outcome of the statistical hypothesis test, The Pvalue is used in hypothesis testing to make a case for the alternative hypothesis, which involves being compared with the α - value.
Lower p values favors the adoption of alternative depending on how extreme th α-value is. The Pvalue is dependent on the value if the test statistic.
|x|+|x+1|+|x+2|+|x+3|+...+|x+2021=2021x
Answer:
jo pahle wale X hai na na X + x plus 1 unhen Yad Karke answer 1 aaega FIR X + 2 =_= + 3 X + 3 yah answer Aaya 1 or 2 X + ka ok
Step-by-step explanation:
FIR hai x+ x and ++ 2021 x
2021x
FIR + Kannan donon ko x
ans
x - 3 X
x - 4042
yah answer aayega ine donon ka the solve this question ok friend
A number plus 16 times its reciprocal equals 8. Find all possible values for the number.
Answer:
4
Step-by-step explanation:
[tex]n+16\frac{1}{n} = 8\\\\n^2+16=8n\\n^2 -8n+16=0\\[/tex]Factorizing we get the answer 4
Which matrix equation represents the system of equations?
{-x+ 2y = 0
y= -2
We are given a system of equations,
[tex]\begin{cases}-x+2y=0\\y=-2\\ \end{cases}[/tex]
This will translate into a 2x2 matrix of coefficients (because 2 equations and 2 unknowns),
[tex]\begin{bmatrix}-1&2\\0&1\\ \end{bmatrix}[/tex]
The matrix will then be applied to the vector (lower dimensions on top),
[tex]\begin{bmatrix}x\\y\\ \end{bmatrix}[/tex]
And the result vector will be whats on the other side of equals sign,
[tex]\begin{bmatrix}0\\-2\\ \end{bmatrix}[/tex]
So to put everything together,
[tex]\begin{bmatrix}-1&2\\0&1\\ \end{bmatrix}\begin{bmatrix}x\\y\\ \end{bmatrix}=\begin{bmatrix}0\\-2\\ \end{bmatrix}[/tex]
Hope this helps :)
Multiply:
2 × (–21) × 7
A)
294
B)
–273
C)
–7
D)
–294
Answer:
[tex]2\times \left(-21\right)\times \:7[/tex]
PEMDAS order of operations:
[tex]2\times \left(-21\right)=-2\times \:21=-42[/tex]
[tex]=-42\times \:7[/tex]
[tex]=-294[/tex]
D) -294 is your answer
OAmalOHopeO
The American Management Association is studying the income of store managers in the retail industry. A random sample of 49 managers reveals a sample mean of $45,420. The standard deviation of the population is known to be $2,050.
a). Compute a 95% confidence interval, as well as the margin of error.
b). Interpret the confidence interval you have computed.
Answer:
a) The 95% confidence interval for the income of store managers in the retail industry is ($44,846, $45,994), having a margin of error of $574.
b) The interval mean that we are 95% sure that the true mean income of all store managers in the retail industry is between $44,846 and $45,994.
Step-by-step explanation:
Question a:
We have 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 p-value 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.
[tex]M = 1.96\frac{2050}{\sqrt{49}} = 574[/tex]
The lower end of the interval is the sample mean subtracted by M. So it is 45420 - 574 = $44,846.
The upper end of the interval is the sample mean added to M. So it is 45420 + 574 = $45,994.
The 95% confidence interval for the income of store managers in the retail industry is ($44,846, $45,994), having a margin of error of $574.
Question b:
The interval mean that we are 95% sure that the true mean income of all store managers in the retail industry is between $44,846 and $45,994.
Quantitative noninvasive techniques are needed for routinely assessing symptoms of peripheral neuropathies, such as carpal tunnel syndrome (CTS). An article reported on a test that involved sensing a tiny gap in an otherwise smooth surface by probing with a finger; this functionally resembles many work-related tactile activities, such as detecting scratches or surface defects. When finger probing was not allowed, the sample average gap detection threshold for m = 8 normal subjects was 1.71 mm, and the sample standard deviation was .53; for n = 10 CTS subjects, the sample mean and sample standard deviation were 2.53 and .87, respectively.
Required:
a. Does this data suggest that the true average gap detection threshold for CTS subjects exceeds that for normal subjects?
b. State and test the relevant hypotheses using a significance level of 0.01.
Answer:
Hence, data does not suggest the true average gap detection threshold for CTS subjects exceeds that for normal subjects.
Step-by-step explanation:
H0 : μ1 = μ2
H1 : μ1 < μ2
Given :
m = 8 ; x1 = 1.71 ; s1 = 0.53
n = 10 ; x2 = 2.53 ; s2 = 0.87
The test statistic :
(x1 - x2) / √(s1²/m + s2²/n)
(1.71 - 2.53) / √(0.53²/8 + 0.87²/10)
-0.82 / √0.1108025
Test statistic = - 0.82 / 0.3328700
Test statistic = - 2.463
The degree of freedom using the conservative approach :
Smaller of (10 - 1) or (8 - 1)
df = 7
TCritical value(0.01, 7) = 2.998
Decision region :
Reject H0 if |Test statistic| > |critical value|
Since, 2.463 < 2.998 ; WE fail to reject H0 ; Hence result is not significant at α = 0.01
