Question 24 of 58
Four classmates collect data by conducting a poll. They
ask students chosen at random how many books they
have to read for English class.
• Kevin interviews 25 students.
• Mary interviews 92 students.
• Sydney interviews 24 students.
• Caleb interviews 31 students.
Whose results are probably the most trustworthy?
O A. Mary's
OB. Sydney's
C. Kevin's
D. Caleb's
SUBMIT
Answers
Mary is more trustworthy because she interviews more students, therefore has a more accurate range of answers.
Related Questions
2.
The reflector of a satellite dish is in the shape of a parabola with a diameter of 4 feet and a depth of 2 feet. To get the maximum reception we need to place the antenna at the focus.
a. Write the equation of the parabola of the cross section of the dish, placing the vertex of the parabola at the origin. Convert the equation into standard form, if necessary. What is the defining feature of the equation that tells us it is a parabola?
b. Describe the graph of the parabola. Find the vertex, directrix, and focus.
c. Use the endpoints of the latus rectum to find the focal width.
d. How far above the vertex should the receiving antenna be placed?
Answers
Answer:
Step-by-step explanation:
Assume the dish opens upwards. The cross-section through the vertex is a parabola. You know three points on the parabola: (0,0), (2,2), and (-2,2). Plug the points into y = ax² + bx + c to get a system of three equations where a=0.5, b=c=0.
Equation of parabola: y = 0.5x²
:::::
Vertex (0,0)
Focal length = 1/(4×0.5) = 0.5
Focus (0,0+0.5) = (0, 0.5)
Directrix y = 0-0.5 = -0.5
:::::
At endpoints of latus rectum, y = 0.5
x = ±√0.5 = ±√2/2
Focal width = 2×√2/2 = √2
:::::
Place antenna at focus, (9,2)
 In one of the examples he is working on, he knows that the two coordinates (0,6) and
(8, 10) are on the function that he is deriving. Using the information from these two
coordinates, determine the slope and y-intercept of the function Mike is looking for, and
then write out the correct function.
Answers
9514 1404 393
Answer:
y = 1/2x + 6
Step-by-step explanation:
The slope m is given by the formula ...
m = (y2 -y1)/(x2 -x1)
m = (10 -6)/(8 -0) = 4/8 = 1/2
The y-intercept is given by the formula ...
b = y -mx
b = 6 -(1/2)(0) = 6
Then the slope-intercept equation is ...
y = mx +b
y = 1/2x +6
7. Ten samples of 15 parts each were taken from an ongoing process to establish a p-chart for control. a. Develop a p-Chart for 95 percent confidence (1.96 standard deviation). b. Based on the plotted data points, what comments can you make
Answers
Answer: Hello the table related to your question is attached below
answer:
a) attached below
b) The process is out of control because two ( 2 ) values from the defect rate table are out of the control limits at 95% as seen in the p-chart in question ( A )
Step-by-step explanation:
a) p-chart for 95% confidence
std = 1.96
Total defects = ∑ number of defective items in the sample = 10
number of samples = 10
sample size ( n ) = 15
The P value for the process is calculated as :
Total defects / ( number of sample * sample size )
= 10 / ( 15 * 10 ) = 10 / 150 = 0.067
standard deviation ( σ ) = [tex]\sqrt{\frac{p(1-p)}{n } } = \sqrt{\frac{0.067(1-0.067)}{15} }[/tex] = 0.065
next we determine the limits ( i.e. upper and lower )
UCL = p + zSp = 0.067 + 1.96(0.065 ) = 0.194
LCL = p - zSp = 0.067 - 1.96(0.065) = -0.060 ≈ 0 ( because LCL ≠ negative)
attached below is the required p-chart
b) The process is out of control because two ( 2 ) values from the defect rate table are out of the control limits at 95% as seen in the p-chart in question ( A )
giả sử tỷ lẹ bệnh nhân tại 1 thành phố là a%
khám ngẫu nhiên b người tại thành phố này tính khả năng 2B + A người có bệnh
Answers
Answer:
ask in English then I can help u
What is 3a to the power of 4 times a to the power of 2
Answers
Answer:ldk
Applying exponential property,
Comparing the base,
Step-by-step explanation:
44y + 321x = 0 biết x=30000
Answers
Answer:
y= -240750/11
Step-by-step explanation:
44y + 321. 30000 = 0
44y = - 963000
y= -240750/11
Determine whether the series is absolutely convergent, conditionally convergent, or divergent.
[infinity]Σ n =1 (-1)^n - 1/n√n
Answers
Answer: hello your question is poorly written attached below is the complete question
answer:
The series is absolutely convergent
Step-by-step explanation:
To determine whether the series is absolutely or conditionally convergent or divergent. apply the Root Test
The series is absolutely convergent
attached below is the solution
Find the area of the shaded regions.
Answers
Answer:
around 22, or 21.98
Step-by-step explanation:
[tex]s1 = {r}^{2} \times \pi = 9 \times 3.14 = 28.26[/tex]
[tex]s2 = 1 \times 3.14 = 3.14[/tex]
[tex]s3 = 28.26 - (3.14 \times 2) = 28.26 - 6.28 = 21.98[/tex]
If a^2+b^2= 4 and ab = 5, what is the value of
(a+b)^2?
A. 10
B. 12
C. 14
D. 16
Answers
Answer:
14
Step-by-step explanation:
(a+b)^2
(a+b)(a+b)
FOIL
a^2 + ab+ab + b^2
Combine like terms
a^2 +2ab + b^2
Rearranging
a^2+b^2 +2ab
We know a^2+b^2 = 4 and ab= 5
4 + 2(5)
4+10
14
Answer:
C. 14.
Step-by-step explanation:
We use the identity:-
a^2 + b^2 = (a + b)^2 - 2ab
So 4 = (a + b)^2 - 2(5)
(a + b)^2 = 4 + 2(5)
= 14.
It has been claimed from previous studies that the average diameter of ball bearings from this manufacturing process is 2.30 cm. Based on the sample of 50 that you collected, is there evidence to suggest that the average diameter is greater than 2.30 cm? Perform a hypothesis test for the population mean at alpha = 0.01.
a. Define the null and alternative hypotheses in mathematical terms as well as in words.
b. Identify the level of significance.
c. Include the test statistic and the P-value.
d. Provide your conclusion and interpretation of the results. Should the null hypothesis be rejected? Why or why not?
Diameters data frame of the first sample (showing only the first five observations)
diameters
0 3.46
1 2.64
2 1.89
3 2.56
4 2.09
Diameters data frame of the second sample (showing only the first five observations)
diameters
0 3.10
1 2.04
2 2.18
3 2.60
4 2.76
test-statistic = 2.06
two tailed p-value = 0.0394
Answers
Data for all 50 samples cannot be obtained, however, the solution below uses the 10 samples below to show how the hypothesis can be tested.
Answer:
Step-by-step explanation:
Average diameter, μ = 2.30
H0 : Average diameter is equal to 2.30cm
H1 : Average diameter is greater than 2.30 cm
The hypothesis :
H0 : μ = 2.30
H1 : μ > 2.30
Using the readings from the data above :
3.46, 2.64, 1.89, 2.56, 2.09, 3.10, 2.04, 2.18, 2.60, 2.76
Sample size, n = 10
Mean, xbar = ΣX/ n = 25.32 / 10 = 2.532
Sample standard deviation, s = 0.4973 (from calculator)
The test statistic :
(xbar - μ) ÷ (s/√(n))
T = (2.532 - 2.30) ÷ (0.4973/√(10))
T = 1.475
The Pvalue :
Degree of freedom, df = n - 1 ; 10 - 1 = 9
Pvalue(1.475, 9) = 0.087
Decision region :
Reject H0 ; If Pvalue < α;
Since 0.087 > 0.01 ; we fail to reject the Null and conclude that there is no evidence to suggest that the average diameter is greater than 2.30 cm
Which graph represents the equation x2 = 8y? On a coordinate plane, a parabola opens up. It has a vertex at (0, 0), a focus at (0, 8), and a directrix at y = negative 8. On a coordinate plane, a parabola opens up. It has a vertex at (0, 0), a focus at (0, 2), and a directrix at y = negative 2. On a coordinate plane, a parabola opens to the right. It has a vertex at (0, 0), a focus at (2, 0), and a directrix at x = negative 2. On a coordinate plane, a parabola opens to the right. It has a vertex at (0, 0), a focus at (8, 0), and a directrix at x = negative 8.
Answers
Answer:
The parabola x²=8y has,
vertex: (0,0)
focus: (0,2)
directrix: y=-2
so that option is the answer,
btw, the parabola opens up to the top and axis of symmetry is x=0
Answer:
It's A!
Step-by-step explanation:
Got it correct on my test! :)
I NEED HELP PLEASE! Can someone help me with the last two red boxes please? The rest of the question is for reference. Thank you for your time!
Answers
Answer:
I think you can go with:
The margin of error is equal to half the width of the entire confidence interval.
so try .74 ± [tex]\frac{.032}{2}[/tex] = [ .724 , .756] as the confidence interval
Step-by-step explanation:
Help anyone know this??
Answers
Answer:
plug n and r into the equation for the answers.
Step-by-step explanation:
Which confidence level would produce the widest interval when estimating the mean of a population based on the mean and standard deviation of a sample of that population? A. 60% B. 70% C. 80% D. 90%
Answers
Answer:
D. 90%
Step-by-step explanation:
it is within the 90th percentile
The confidence level of D. 90% would produce the widest interval when estimating the mean of a population from the mean and standard deviation of a sample of that population.
What is Confidence Interval?Confidence interval in statistics is defined as the certain range of values that you estimate for the unknown parameter lies within.
From the definition of the confidence interval itself, it is clear that the level with the widest interval will be the highest confidence level.
So if you need a wider interval for estimating the mean of a population from the mean and standard deviation, you need to take higher confidence level.
Here the options are 60%, 70%, 80% and 90%.
Here, the highest level is 90% which is the highest among the given levels.
Hence the confidence level is option D. 90%.
To learn more about Confidence Interval, click here :
https://brainly.com/question/22851322
#SPJ7
Angles CED and CBD subtend the same arc. Determine the measure of ∠CED.
Question options:
1)
100°
2)
150°
3)
310°
4)
50°
Answers
Answer:
[tex]50^{\circ}[/tex]
Step-by-step explanation:
Inscribed angles that form the same arc have the same angle measure, no matter where they lie on the circle. Since the measure of angle CBD forms the same arc as angle CED, the measure of angle CBD must be equal to the measure of angle CED, hence [tex]m\angle CED=\boxed{50^{\circ}}[/tex]
Answer:
the answer is 4)50°
Step-by-step explanation:
because it is same
Hi I need help this is a FOIL problem
Answers
Answer:
you should be able to find the mistake if you know FOIL well
Step-by-step explanation:
F: first digit in both binomials
O: outermost digits in both binomials
I: two most innermost digits
L: last two digits in both binomials
Hector's Position:
Hector was standing halfway between first and second base, at the grass line. The
grass line is 95 feet from the pitcher's mound.
6. Calculate the coordinates for Hector's position. [Note: We can assume that 95
feet is an approximately horizontal distance from the pitcher's mound to the grass
line.] (2 points: 1 for x, 1 for y)
Hector was standing at the coordinate ( __, _).
Calculate Hector's Throw:
Answers
Answer:
(137.78, 47.72)
Step-by-step explanation:
(I just finished this assignment.)
Tre's position at the pitcher's mound as the point (42.78, 42.78).
( x , y )
Hector is about 95 feet away from the pitcher's mound horizontal, (x axis).
Since we already have the correct y-coordinate, we need to solve for the correct x-coordinate.
x = 95 + 42.78
↓ ↓ ↓
95 + 42.78 = 137.72
Now all you need to do is write out the coordinates.
Hector's coordinates are (137.72, 47.78 )
Hi! I would appreciate if you could solve this for me. The question I need help with is question 41. Thank you. :)
Answers
Answer:
Expression: 7+7+9.5+6+9.5
Evaluation: 39 cm
Step-by-step explanation:
Let's write the numerical expression for the figure to the right. The perimeter is the addition of all sides of the figure. Therefore, we write 7+7+9.5+6+9.5 for our expression.
Now, to evaluate the expression, we just add them together. 7+7+9.5+6+9.5=39 cm.
a special window in the shape of a rectangle with semicircles at each end is to be constructed so that the outside perimeter is 100 feet. find the dimensions of the rectangle tha tmaximizes the total area of the window
Answers
Answer:
The dimensions of the rectangle are length 25 feet and width 15.92 feet
Step-by-step explanation:
Let L be the length of the rectangle and w be the width.
The area of the rectangular part of the shape is Lw while the area of the two semi-circular ends which have a diameter which equals the width of the rectangle is 2 × πw²/8 = πw²/4. The area of each semi-circle is πw²/4 ÷ 2 = πw²/8
So, the area of the shape A = Lw + πw²/4.
The perimeter of the shape, P equals the length of the semi-circular sides plus twice its length. The length of a semi-circular side is πw/2. So, both sides is 2 × πw/2 = πw
P = πw + 2L
Since the perimeter, P = 100 feet, we have
πw + 2L = 100
From this L = (100 - πw)/2
Substituting L into A, we have
A = Lw + πw²/4.
A = [(100 - πw)/2]w + πw²/4.
A = 50w - πw²/2 + πw²/4.
A = 50w - πw²/2
Now differentiating A with respect to w and equating it to zero to find the value of w which maximizes A.
So
dA/dw = d[50w - πw²/2]/dw
dA/dw = 50 - πw
50 - πw = 0
πw = 50
w = 50/π = 15.92 feet
differentiating A twice to get d²A/dw² = - π indicating that w = 50/π is a value at which A is maximum since d²A/dw² < 0.
So, substituting w = 50/π into L, we have
L = (100 - πw)/2
L = 50 - π(50/π)/2
L = 50 - 50/2
L = 50 - 25
L = 25 feet
So, the dimensions of the rectangle are length 25 feet and width 15.92 feet
2. Solve for z and express your answer in interval notation: 10 – 4z<20
Answers
Answer:
I belive its z > -5/2
Step-by-step explanation:
First subtract 10 from both sides.
Then simplify
Then multiply both sides by -1 because you're reversing the inequality
simplify again
Then divide both sides by 4
Finally you simplify to get
z > -5/2
:)
Choose the correct correspondence
Answers
Answer:
The Answer is K.
Step-by-step explanation:
K is the answer because it is the only other point on the line DK
A population of bacteria contains 80 bacteria in generation 1 and triples in
population every generation. This sequence represents the number of
bacteria for the first few generations:
80, 240, 720, ...
What is the explicit formula for the number of bacteria in generation n?
A. a(n) = 80 + (n - 1)3
B. a(n) = 3.801-1
C. a(n) = 3 + (n-1)80
D. a(n) = 80.30-1
Answers
Answer:
A
Step-by-step explanation:
Answer:a(n)=80•3n-1
Step-by-step explanation:
Find the absolute maximum and absolute minimum for f (x )equals x cubed minus 2 x squared minus 4 x plus 2 on the interval 0 less or equal than x less or equal than 3.
Answers
9514 1404 393
Answer:
maximum: 2minimum: -6Step-by-step explanation:
The extrema will be at the ends of the interval or at a critical point within the interval.
The derivative of the function is ...
f'(x) = 3x² -4x -4 = (x -2)(3x +2)
It is zero at x=-2/3 and at x=2. Only the latter critical point is in the interval. Since the leading coefficient of this cubic is positive, the right-most critical point is a local minimum. The coordinates of interest in this interval are ...
f(0) = 2
f(2) = ((2 -2)(2) -4)(2) +2 = -8 +2 = -6
f(3) = ((3 -2)(3) -4)(3) +2 = -3 +2 = -1
The absolute maximum on the interval is f(0) = 2.
The absolute minimum on the interval is f(2) = -6.
1000 randomly selected Americans were asked if they believed the minimum
wage should be raised. 600 said "yes." What is the 99% confidence interval
for the proportion of Americans who believe that the minimum wage should
be raised?
Answers
Answer:i dont now
Step-by-step explanation:
A silo is built in the shape of a cylinder with a cone for a roof. If the height of the
cylinder is 5 m, the radius is 2.8 m and the slant height of the cone is 6,6 m,
determine the amount of material needed to create the rounded sides and conical
roof, Round to the nearest tenth of a cubic m.
Answers
9514 1404 393
Answer:
146.0 m²
Step-by-step explanation:
The lateral areas of the cylinder and cone are given by the formulas ...
A = πrs . . . . cone area; radius r, slant height s
A = 2πrh . . . . cylinder area; radius r, height h
__
The total area lateral area of the silo is ...
A = π(2.8 m)(6.6 m) +2π(2.8 m)(5 m) = π(2.8 m)(6.6 m +2(5 m)) = 46.48π m²
A ≈ 146.0 m² . . . area of sides and roof of silo
_____
Additional comment
The answer is requested in cubic meters. Area has units of square meters. There is nothing in this problem statement that seems to be requesting a volume, which is what would have units of cubic meters.
I need the help ASAP please
Answers
Answer:
Option B
Answered by GAUTHMATH
There are 160 pages in a book.15% of the pages having pictures on them. How many
Pages do not have pictures on them?
Answers
Answer:
136
Step-by-step explanation:
15/100×160
=24
pages that doesn't have pictures=160-24
=136
Will give brainliest answer
Answers
Answer:
14 hours
Step-by-step explanation:
Take any two consecutive high tides and to find their x coordinatey and sub them..
Determine whether the following individual events are independent or dependent. Then find the probability of the combined event.
Randomly drawing and immediately eating two red pieces of candy in a row from a bag that contains red pieces of candy out of pieces of candy total.
Answers
Answer:
Dependent event
[tex]P(Red = 2) = \frac{5}{588}[/tex]
Step-by-step explanation:
Given
[tex]Total = 49[/tex]
[tex]Red = 5[/tex]
Solving (a): Are the events dependent?
Yes, they are.
When the first red candy is selected and eaten, the total number of candies reduced to 48 and the number of red candies also reduced to 4.
So, the probability of selecting a 2nd candy is dependent on the first candy selected.
Solving (b): P(Red = 2)
This is calculated as:
[tex]P(Red = 2) = P(Red) * P(Red | Red)[/tex]
The first selection has the following probability:
[tex]P(Red) = \frac{Red}{Total}[/tex]
[tex]P(Red) = \frac{5}{49}[/tex]
The second selection has the following probability:
[tex]P(Red|Red) = \frac{Red - 1}{Total - 1}[/tex]
[tex]P(Red|Red) = \frac{5 - 1}{49 - 1}[/tex]
[tex]P(Red|Red) = \frac{4}{48}[/tex]
So, we have:
[tex]P(Red = 2) = P(Red) * P(Red | Red)[/tex]
[tex]P(Red = 2) = \frac{5}{49} * \frac{4}{48}[/tex]
Reduce fraction
[tex]P(Red = 2) = \frac{5}{49} * \frac{1}{12}[/tex]
Multiply
[tex]P(Red = 2) = \frac{5}{588}[/tex]
f(x) = x - 1. Find the inverse of f(x).
Answers
Answer:
f^-1 (x) = x+1
Step-by-step explanation:
f(x) = x-1
y = x-1
Exchange x and y
x = y-1
Solve for y
Add 1 to each side
x+1 = y-1+1
x+1 = y
The inverse is x+1
f^-1 (x) = x+1
