a sample that excludes subjects that are not part of the population being measured.
A researcher planned a study in which a crucial step was offering participants a food reward. It was important that three food rewards were equal in appeal. Thus, a pilot study was designed in which participants were asked which of the rewards they preferred. The observed frequencies are as follows:
Of the 60 participants, 16 preferred cupcakes, 26 preferred candy bars, and 18 favored dried apricots.
1. The appropriate statistical test for this problem is (be specific): ________.
2. What are the expected frequencies for this question?
3. What is the cutoff on the comparison distribution (step 3)?
4. What is the correct calculation for chi-square (step 4)?
Answer:
Step-by-step explanation:
Hello!
A pilot study was conducted to test if three food rewards are equally appealing to the participants.
Of 60 participants surveyed:
16 preferred cupcakes (CC)
26 preferred candy bars (CB)
18 preferred dried apricots (DA)
If the three types of food are equally appealing for the participants, you'd expect that their proportions will be equal: P(CC)=P(CB)=P(DA)= 1/3
1.
The objective of this pilot study is to test if the observed frequencies follow a theoretical model/ distribution. To analyze this, you have to apply a Chi Square Goodness to Fit test. [tex]X^2=sum \frac{(O_i-E_i)^2}{E_i} ~~X^2_{k-1}[/tex] Where k= number of categories of the variable.
For this example the statistical hypotheses are:
H₀: P(CC)=P(CB)=P(DA)= 1/3
H₁: At least one of the proportions isn't equal to the others.
2.
To calculate the expected frequencies for each category you have to use the formula: [tex]E_i= n* P_i[/tex] where Pi represents the theoretical proportion for the i category, stated in the null hypothesis.
[tex]E_{CC}= n* P(CC)= 60*1/3= 20[/tex]
[tex]E_{CB}= n*P(CB)= 60*1/3= 20[/tex]
[tex]E_{DA}= n* P(DA)= 60* 1/3= 20[/tex]
3.
The cutoff or critical value indicates the beginning of the rejection region for the hypothesis test. For the Chi-Square tests, the rejection region is always one-tailed to the right, meaning that you'll reject the null hypothesis if the value of the statistic is big. For the goodness to fit test you have k-1 degrees of freedom, so the critical value will be:
Assuming α: 0.05
[tex]X^2_{k-1;1-\alpha /2}= X^2_{2;0.975}= 7.378[/tex]
The rejection region is then X²₂ ≥ 7.378
4.
[tex]X^2_{H_0}= \frac{(O_{CC}-E_{CC})^2}{E_{CC}} + \frac{(O_{CB}-E_{CB})^2}{E_{CB}} + \frac{(O_{DA}-E_{DA})^2}{E_{DA}} = \frac{(16-20)^2}{20} +\frac{(26-20)^2}{20} +\frac{(18-20)^2}{20}= \frac{14}{5}= 2.8[/tex]
I hope this helps!
Ramesh examined the pattern in the table. Powers of 7 Value 7 Superscript 4 2,401 7 Superscript 3 343 7 Superscript 2 49 7 Superscript 1 7 7 Superscript 0 1 7 Superscript negative 1 StartFraction 1 Over 7 EndFraction Ramesh says that based on the pattern 7 Superscript negative 5 = negative 16,807. Which statement explains whether Ramesh is correct? Ramesh is correct because 7 Superscript negative 5 is equivalent to Negative 7 times (negative 7) times (negative 7) times (negative 7) times (negative 7), which has the same value as Negative 16,807. Ramesh is correct because as the exponents decrease, the previous value is divided by 7, so 7 Superscript negative 5 = 1 divided by 7 divided by 7 divided by 7 divided by 7 divided by 7 = negative 16,807. Ramesh is not correct because 7 Superscript negative 5 is equivalent to StartFraction 1 Over 7 Superscript 5 EndFraction, which has the same value as StartFraction 1 Over 7 Superscript 4 EndFraction divided by 7 = StartFraction 1 Over 7 cubed EndFraction = StartFraction 1 Over 343 EndFraction. Ramesh is not correct because as the exponents decrease, the previous value is divided by 7, so 7 Superscript negative 5 = 1 divided by 7 divided by 7 divided by 7 divided by 7 divided by 7 = StartFraction 1 Over 16,807 EndFraction. NEED HELP NOW PLEASE I HAVE ONLY SEEN WRONG ANSWERS
Answer:
D
Step-by-step explanation:
Answer:
D.- Ramesh is not correct because as the exponents decrease, the previous value is divided by 7, so 7^-5 = 1 ÷ 7 ÷ 7 ÷ 7 ÷ 7 ÷ 7 = 1/16,807.
Ameeta finished 12 math problems. David finished 3 times as many. How many more math problems did David finish than Ameeta?
Answer:
24
Step-by-step explanation:
Ameeta = 12 math problems.
David =12×3=36 math problems
So 36-12=24
Answer:
12
David's
3 times longer
comparison problem
Step-by-step explanation:
got right on edge
Plz help ..............!!!!!
Answer:
1.8
is the median
Answer: 1.8
Step-by-step explanation: 1.8 is the median
The Australian Open is the first of the four Grand Slam professional tennis events held each year. Victoria Azarenka beat Maria Sharapova to win the 2012 Australian Open women’s title. During the tournament Ms. Azarenka serve speed reached kilometers per hour. A list of the Women’s Singles serve speed for the 2012 Australian Open is provided below. Player Serve Speed (km/h) S. Williams 192 S. Lisicki 192 M. Keys 191 L. Hradecka 188 J. Gajdosova 187 J. Hampton 187 B. Mattek-Sands 185 F. Schiavone 185 P. Ormaechea 185 P. Parmentier 185 N. Petrova 183 G. Arn 183 V. Azarenka 182 A. Ivanovic 182 P. Kvitova 179 M. Krajicek 179 V. Dushevina 178 S. Stosur 176 S. Cirstea 176 M. Barthel 175
a. Compute the mean, variance, and standard deviation for the serve speeds.
b. A similar sample of the 20 Women’s Singles serve speed leaders for the 2011 Wimbledon tournament showed a sample mean serve speed of 182.5 kilometers per hour. The variance and standard deviation were 33.3 and 5.77, respectively. Discuss any difference between the serve speeds in the Australian Open and the Wimbledon women’s tournaments.
Answer:
asnwer is B
Step-by-step explanation:
mark BRAINLIEST
Giving brainliest to CORRECT answer.
Answer:
A. 2
Step-by-step explanation:
[tex] y = 16x^2 - 8x + 1[/tex] is a quadratic function, hence on solving it will give two zeros, therefore graph of the function will intersect x axis in two points.
Javier is 175% heavier than his brother. If Javier’s brother weighs 80 pounds, how much does Javier weigh?
Answer:
140
Step-by-step explanation:
175% of 80 = 140
What is true when you rent? A.you build equity in your house,B.you are responsible for any repairs,c. You pay fewer up front costs
Answer: C you pay fee fewer upfront cost
Step-by-step explanation:
Please help worth 20 points!!
Answer:I would think u would
Step-by-step explanation:42,500×26
Answer:
1634.62$
Step-by-step explanation:
P=S/n
P=42500/26=1634.62
plzz help its timed ill give brainliest
The points (8.1) and (8, 11) lie on a circle with a radius of 5. Find the center of the circle
Answer:
(8, 6)
Step-by-step explanation:
First, we find the distance between the two points.
Both have the same x-coordinate, 8, so the distance is simply the difference in y.
|11 - 1| = 10
The distance between the points is 10.
Since the radius of the circle is 5, the greatest distance between two points on the circle is 10, and the two points must be the endpoints of a diameter.
The midpoint of a diameter is the center of the circle.
(1 + 11)/2 = 12/2 = 6
The center o the circle is (8, 6).
Solve.
A European swallow flies about 12 meters in 1 second.
How many kilometers could it fly in 15 minutes?
It could fly |
Answer:
It could fly 10,8 kilometers.
Step-by-step explanation:
The European swallow fly speed is 12 meters per second.
We have to calculate how many kilometers it could fly in 15 minutes.
This can be calculated using the equivalent factors for each of the units:
- 1 km is equivalent to 1,000 meters.
- 1 minute is equivalent to 60 seconds.
We know that the distance travelled by the fly is the product of the speed and the time, so we have:
[tex]D=v\cdot t\\\\\\D=12\,\dfrac{m}{s}\cdot15\, min\\\\\\D=12\,\dfrac{m}{s}\cdot(\dfrac{1\,km}{1,000\,m})\cdot15\, min\cdot (\dfrac{60\,s}{1\,min})\\\\\\D=\dfrac{12\cdot 15\cdot 60}{1,000}\,km=\dfrac{10,800}{1,000}\,km\\\\\\D=10,8 \,km[/tex]
Which equation describes a line
that passes through (0, 3) and is
perpendicular to the line described
by y = -5x - 4?
Answer:
A line has equation y = ax + b, perpendicular to the line y = -5x - 4
=> a x (-5) = -1 => a = 1/5.
This line passes (0, 3) => (1/5)*0 + b = 3 => b = 3
=> Equation of this line: y = (1/5)x + 3
Hope this helps!
:)
The equation of the line passes through the point (0, 3) and is perpendicular to the line → y = - 5x - 4 is y = x/5 + 3.
What is the general equation of a straight line?The general equation of a straight line is -
y = mx + c
Given is a line that passes through (0, 3) and is perpendicular to the
line → y = - 5x - 4
Since the line is perpendicular to the line → y = - 5x - 4. We can write -
m[L] = -1/-5
m[L] = 1/5
Assume that the equation of the line is -
y = m[L]x + c
y = x/5 + c
Since the line passes through the point (0, 3), we can write -
3 = 0 + c
c = 3
The final equation of the line will be -
y = x/5 + 3
Therefore, the equation of the line passes through the point (0, 3) and is perpendicular to the line → y = - 5x - 4 is y = x/5 + 3.
To solve more questions on Straight lines, visit the link below-
https://brainly.com/question/27730503
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On circle OOO below, the measure of \stackrel{\LARGE{\frown}}{FJ} FJ ⌢ F, J, start superscript, \frown, end superscript is 84^\circ84 ∘ 84, degrees. The measure of \stackrel{\LARGE{\frown}}{GH} GH ⌢ G, H, start superscript, \frown, end superscript is 76^\circ76 ∘ 76, degrees. What is the measure of \angle HKJ∠HKJangle, H, K, J?
Answer:
100°
Step-by-step explanation:
The angle between chords is the average of the intersected arc angles.
∠FKJ = ½ (84° + 76°)
∠FKJ = 80°
∠HKJ is supplementary to ∠FKJ.
∠HKJ = 180° − 80°
∠HKJ = 100°
An mp3 player is on sale for 30% off the regular price of $39.98. How much is the discount?
Answer:
$27.98
Step-by-step explanation:
100 - 30 in price %=70%
Price will be 70% of original regular price
$39.98 * .7 = answer
Answer:
Discount is $11.99
Total is now $27.99
Step-by-step explanation:
To find the discount, you find out what 30% is of 39.98, so you multiply
39.98 x 30%(or .3) = 11.994
39.98- 11.99= 27.99
Which unit would be best for measuring the thickness of a coin?
kilometer
()) centimeter
meter
)) milli
Answer:
Since 1 mm = . 03937 inches, mm would seem to be the units appropriate for defining the thickness of a coin measuring 2 units.
Step-by-step explanation:
Which number line correctly shows 0.8 + 0.3?
Answer:
the second answer
Step-by-step explanation:
cause 0+0.8 is 0.8 and 0.8+0.3 is 1.1
Answer:
A
Step-by-step explanation:
What’s the correct answer for this?
Answer:
A.
Step-by-step explanation:
tan x= 6/8
usually tan θ = perpendicular / base
So,
we get perpendicular = 6, base = 8
Now using Pythagorean Theorem to find hypotenuse
hyp² = base² + Perp²
hyp² = 8² + 6²
hyp²= 64 + 36
hyp²=100
Taking sq root on both sides
hypotenuse = 10
Now
sin θ = Perpendicular / Hyp
sin x = 6 / 10
Now
cos θ = base / Hyp
cos x = 8 / 10
You have 9 pets:
4 fish,
1 cat,
2 dogs
and 2 birds. What is the probability a pet chosen at random is a dog or a four legged pet?
Answer:
1/3
Step-by-step explanation:
4 fish, 1 cat,2 dogs,and 2 birds = 9
dogs or 4 legged = cats and dogs = 1+2 = 3
P(dog or 4 legged) = number of dogs or 4 legged / total
=3/9
=1/3
Answer:
⅓
Step-by-step explanation:
Total pets:
4+1+2+2 = 9
Dog or four legged pets: 2 + 1 = 3
Probability: 3/9 = 1/3
how many square feet of of outdoor carpet will we need for this hole?
Answer:
To convert the feet to square feet we have to multiply the length by the width. In which, we should get the answer as well.
Our length is 2ft, since it's a rectangle the other side is 2ft as well.
The width is 3ft, and the other half is 3ft.
So, basically to get the area of the hole, it'd be 3*2=
Which, it's 6sq ft.
Step-by-step explanation:The actual answer is 36. If I am wrong i am sorry ;3
2x + 3y = 12
Complete the missing value in the solution to the equation.
,8)
Is z = 5 in the solution set of the inequality 6z > 15
YES
OR
NAA
Answer:
Yes
Step-by-step explanation:
6z > 15
z > 15/6
z > 2.5
So all numbers greater than 2.5 is in the solution set of the inequality 6z > 15.
You roll a six-sided number cube (die). What is the BEST answer for the probability that the number rolled is between 1 and 6, inclusive?
A) certain
B) unlikely
C) impossible
D) very likely
Answer: It is A certain.
Step-by-step explanation:
Because all the numbers on a six-sided cube is between 1 and 6 so it is certain or 100/100 that the number will land on a number between 1 and 6.
Which formula will find the area of the composite figure below ?
Answer:
Last formula
[tex] {side}^{2} + \frac{\pi {r}^{2} }{2} [/tex]
Step-by-step explanation:
Composite figure is made up of a square and a semicircle.
Therefore,
Area of composite figure= area of square + area of semicircle
[tex] \huge\purple {\boxed {= {side}^{2} + \frac{\pi {r}^{2} }{2}}} [/tex]
Hannah is setting up chairs for the class play. The room has 20 chairs. What are the different ways she can arrange the chairs in a rectangle?
Answer:
Have them 4 by 5.
Step-by-step explanation:
If you she but 5 chairs in a row, then 3 on the side of the chairs. That would create a backward "L" type of shape.
For example, (The "o" is a chair)
OOOOO
O
O
O
As you see the the top are the 5 chairs, then side are are the 4 chairs.
Then, you will do the exact same thing but on the opposite side.
Here is the next example.
OOOOOO
O O
O O
O O
OOOOOO
Basically, arranging the chairs 4x5, it would make a rectangle.
If a pair of standard dice are rolled,
what is the probability that at least
one die shows a 5?
?
Answer:
The correct answer is 11/36
Step-by-step explanation:
The probability that at least one die shows a '5' is 11/36.
What is the probability of an event?The probability of an event is the chance of happening that particular event.
Here, a pair of standard dice are rolled.
Therefore, the total number of combinations of two dice is = 6² = 36.
The case at which one die shows a '5' are: (1, 5); (2, 5); (3, 5); (4, 5); (5, 5); (6,5); (5, 1); (5, 2); (5, 3); (5, 4); (6, 5)
Therefore, the total number of cases at which one die shows a '5' is = 11.
Therefore, the required probability of the given event is
= 11/36
Learn more about the probability of an event here: https://brainly.com/question/9548010
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A car can travel 480 miles on a full tank of petrol. The tank holds 60 litres. A driver fills the tank and sets off on a journey. How many litres of petrol will be left when the car has travelled 360 miles?
Answer:
15 liters
Step-by-step explanation:
60/480= 0.125
0.125*360= 45
60-45= 15
Do you remember the difference between a row and a column
in Math?
Answer:
Rows are the steps - they go left to right and are numbered 1,2,3,... Columns are the columns - they go up and down and are lettered A,B,C,... Cells are defined by the row and column they are in.
Step-by-step explanation:
Plz answer BRAINLIEST Choose the statement that is true of both triangles.
9514 1404 393
Answer:
A. Side lengths of 4 units and 2 units and a nonincluded angle of 30°
Step-by-step explanation:
Both triangles have sides marked 2 units and 4 units, but the angle is not between them. The angle is opposite the short side in one triangle (which will be a right triangle), and opposite the long side in the other triangle (which will be an obtuse triangle). The sides and angles of the two triangles will not have the same measures, and neither will have an angle of 100°.
The first description is appropriate:
Side lengths of 4 units and 2 units and a nonincluded angle of 30°
Suppose the round-trip airfare between Philadelphia and Los Angeles a month before the departure date follows the normal probability distribution with a mean of $387.20 and a standard deviation of $68.50. What is the probability that a randomly selected airfare between these two cities will be between $325 and $425?
Answer:
52.74% probability that a randomly selected airfare between these two cities will be between $325 and $425
Step-by-step explanation:
Problems of normally distributed samples are solved using the z-score formula.
In a set with mean [tex]\mu[/tex] and standard deviation [tex]\sigma[/tex], the zscore 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 pvalue, we get the probability that the value of the measure is greater than X.
In this question, we have that:
[tex]\mu = 387.20, \sigma = 68.50[/tex]
What is the probability that a randomly selected airfare between these two cities will be between $325 and $425?
This is the pvalue of Z when X = 425 subtracted by the pvalue of Z when X = 325. So
X = 425
[tex]Z = \frac{X - \mu}{\sigma}[/tex]
[tex]Z = \frac{425 - 387.20}{68.50}[/tex]
[tex]Z = 0.55[/tex]
[tex]Z = 0.55[/tex] has a pvalue of 0.7088
X = 325
[tex]Z = \frac{X - \mu}{\sigma}[/tex]
[tex]Z = \frac{325 - 387.20}{68.50}[/tex]
[tex]Z = -0.91[/tex]
[tex]Z = -0.91[/tex] has a pvalue of 0.1814
0.7088 - 0.1814 = 0.5274
52.74% probability that a randomly selected airfare between these two cities will be between $325 and $425
