The authors of a paper studied a random sample of 350 Twitter users. For each Twitter user in the sample, the "tweets" sent during a particular time period were analyzed and the Twitter user was classified into one of the following categories based on the type of messages they usually sent.
Category Description
IS Information sharing
OC Opinions and complaints
RT Random thoughts
ME Me now (what I am doing now)
O Other
The accompanying table gives the observed counts for the five categories (approximate values read from a graph in the paper).
Twitter Type IS OC RT ME O
Observed count 50 61 64 102 73
Required:
Carry out a hypothesis test to determine if there is convincing evidence that the proportions of Twitter users falling into each of the five categories are not all the same. Use a significance level of 0.05.
Answer:
The null hypothesis is rejected.
Step-by-step explanation:
Assuming the proportions in each of the categories is the same which is 1/5 = 0.20.
H0: p1 = p2 = p3 = p4 = p5 = 0.2
Ha: H0 is not true.
The table is as below:
Twitter Type: Observed Count p E=350*p (O-E)^2/E
IS 50 0.2 70 5.7143
OC 61 0.2 70 1.1571
RT 64 0.2 70 0.5143
ME 102 0.2 70 14.6285
O 73 0.2 70 0.1286
-----------------------------------------------------------------------------------------------
Total 22.1428
The test statistic [tex]\chi^2[/tex] is 22.1421
The degree of freedom d is n-1=5-1 =4
The corresponding p-value from the chi-squared table is .000188.
As this value is less than the p-value for the H0 thus we reject the null hypothesis.
A group of transfer bound students wondered if they will spend the same mean amount on texts and supplies each year at their four-year university as they have at their community college. They conducted a random survey of 54 students at their community college and 66 students at their local four-year university. The sample means were $947 and $1,011, respectively. The population standard deviations are known to be $254 and $87, respectively. Conduct a hypothesis test to determine if the means are statistically the same assume alpha is 0.05.
Answer:
We accept H₀. We don´t have enough evidence to support the difference between the two means
Step-by-step explanation:
Group 1 : Comunity College
Sample:
size : n₁ = 54
Sample mean x₁ = 947
Sample standard deviation s₁ = 254
Group 2 : Local University
Sample
size : n₂ = 66
Sample mean : x₂ = 1011
Sample standard deviation s₂ = 87
Significance level α = 0,05 α = 5 % CI = 95 %
Both samples are with n> 30 so we can use z table for the test
from z-table we find z(c) = 1,96
The problem statement establishes to run a hypothesis test to determine if the means are statistically the same ( or different) then we use two-tail-test
Hypothesis Test
Null Hypothesis H₀ x₁ - x₂ = 0 or x₁ = x₂
Alternative hypothesis Hₐ x₁ - x₂ ≠ 0 or x₁ ≠ x₂
To calculate
z(s) = ( x₁ - x₂ ) / √ s₁²/n₁ + s₂²/n₂ )
z(s) = 947 - 1011 / √ (254)²/54 + (87)² / 66
z(s) = - 64 /√ 1194,74 + 114,68
z(s) = - 64 / 36,185
z(s) = - 1,77
Comparing modules of |z(c)| and |z(s)|
z(s) < z(c)
Then z(s) is in the acceptance region we accept H₀ . There is not enough evidence to support differences in the means of the two groups
A marine biologist wants to test the effect of water temperature on the length of time sea otters can remain under water during a dive. He gathers data on randomly selected dives by 7 different otters, recording dive duration (in seconds) and water temperature (in degrees Celsius). A computer regression analysis of his data is given below. Assume all conditions for inference for slope have been met.
Predictor Coef SE coef T P
Constant 52.789 5.257 10.04 0.000
Water temp 3.3684 0.4216 7.990 0.002
S= 5.557 R- Sq= 92.7% R-Sq(adj)= 91.3%
Required:
What is the estimate of the standard deviation of the sampling distribution of b, the slope of the sample regression line for this relationship?
Answer:
0.4216
Step-by-step explanation:
from the data given The estimate of the standard deviation of the sampling distribution of b,
( The slope of the sample regression line for the relationship )
= 0.4216 ( i.e. intersection of SE coef and water temperature )
Testing the effect of water temperature on the length of time sea otters can remain
13.) In 1990, a radio costs $25. Now,
the radio costs $5. What is the
percent of change?
Answer:
Step-by-step explanation:
80% of 25 = 5
because 10% of 25 = 2.5
and then 10 x 8 = 80
so 2.5 x 8 = 20
25 - 20 = 5
therefore, the percentage change is 80%
GIVE BRAINLIEST
hope this helped,
-cheesetoasty
Someone pls help me out thanks
Answer:
C(7,-8)
R= 8
The general formula of a circle = (x-a)+(y-b)=r²
Find the value of x in the triangle shown below.
a. x=80
b. x=48
c. x= 32
d. x=12
h.c gjsussisuse udrih eieeiee Getty e
50 Points! Will give brainliest!
Answer:
D.
Step-by-step explanation:
A recipe for cookies calls for 2/3 cups of sugar per batch Atlanta use 4 cups of sugar to multiply batches of cookies how many batches will she make
6
Step-by-step explanation:
What is the volume of a rectangular prism with length equal to 13,width equal to 6 and height equal to 4
Given:
Length of the rectangular prism = 13 units.
Width of the rectangular prism = 6 units.
Height of the rectangular prism = 4 units.
To find:
The volume of the rectangular prism.
Solution:
We know that the volume of the rectangular prism is:
[tex]V=l\times b\times h[/tex]
Where, l is length, b is breadth or width and h is the height of the rectangular prism.
Putting [tex]l=13,b=6,h=4[/tex] in the above formula, we get
[tex]V=13\times 6\times 4[/tex]
[tex]V=312[/tex]
Therefore, the volume of the given rectangular prism is 312 cubic units.
A data set contains the values 1, 2, 5, 5, and 7.
The table shows the distance between each value and the mean of 4.
Data value
Distance between
value and mean
1
3
2
2.
5
1
5
1
7
3
Sum of distances 10
What is the mean absolute deviation (MAD) of the data set?
Answer:
2, The MAD is the MEAN STANDARD DEVIATION meaning it is the average of all the numbers distances away from the MEAN. you just add up all the distances and divide by how many there are.
a triangle has two sides of lengths 5 and 12, what value could the length of the third side be? check all that apply
Answer:
11 and 9
Step-by-step explanation:
The inequality is 12-5<x<12+5, which simplifies to 7<x<17, so the length of the third side can be any number between 7 and 17, but not including those numbers.
The answer is 11 and 9
4x^2+ xy+81y^2 find the missing number
Answer: (9y^4*x^6)^2
Step-by-step explanation: First you take the square root of 81, which is 9. Next, you divide 8 and 12 by 2. Lastly, you multiply everything together, and you get a final answer of (9y^4*x^6)^2. Do you do RSM?
Help :)))))))
And branlist wil come!!
Answer:
y * 2.5 = x
Step-by-step explanation:
y= inch
x= conversion from inch to cm
1. What is the difference in the ranges?
A 5 points
C 20 points
B 10 points
D 35 points
2. Which test has a greater median?
A Test 1
B Test 2
C They have the same median.
D You cannot tell from the dot plots.
The temperature decreased by 4.6 degrees Fahrenheit
B The temperature decreased by 0.28 degrees Fahrenheit
The temperature increased by 0.75 degrees Fahrenheit
The temperature increased by 4.6 degrees Fahrenheit
Answer:
10.23
Step-by-step explanation:
just add them togather
In a random sample of 10 residents of the state of Florida, the mean waste recycled per person per day was 2.1 pounds with a standard deviation of 0.59 pounds. Determine the 98% confidence interval for the mean waste recycled per person per day for the population of Florida. Assume the population is approximately normal. Step 1 of 2 : Find the critical value that should be used in constructing the confidence interval. Round your answer to three decimal places.
the area of the trangle is......
Answer:
30 cm²
Step-by-step explanation:
To find the area of a triangle, multiply the base and the height, then, divide the product by 2.
In this case, the base is 6 and the height is 10.
6 x 10 = 60
The product is 60.
60 / 2 = 30
Therefore, the area of this triangle is 30 cm².
Answer:
30
Step-by-step explanation:
Formula for area of a triangle: [tex]A=\frac{bh}{2}[/tex]
where b = base length and h = height
The triangle shown has a base length of 6 cm and a height of 10 cm
Using this information we plug in the values into the formula
So...
[tex]A=\frac{10*6}{2} \\10*6=60 \\\frac{60}{2} =30[/tex]
Hence, the area of the triangle is 30 square centimeters.
PLSS HELP ASAP!!
13 points when answered:) Thank you!!
Answer:
The wright answer is A
Step-by-step explanation:
[tex] \sqrt{20} = 4.47 \\ \frac{14}{3} = 4.67 \\ 4.47 < 4.5 < 4.67[/tex]
which can be used to find the perimeter of the rectangle?
Answer:
Step-by-step explanation:
2 ( 5 plus 13)
Brainlist?
Jerome is painting a rectangular toolbox that is 20 inches by 10 inches by 8 inches. and a tube of paint covers 300 square inches. What is the surface area? and how many tubes of paint should Jerome buy?
Answer:
He should buy 3 tubes of paint.
Step-by-step explanation:
20×10×8=880
880÷300=2.93
2.93≈3
So, Jerome should buy 3 tubes of paint.
Brainliest please!
What is the value of x in the triangle?
Answer:
C) 7[tex]\sqrt{2}[/tex]
Step-by-step explanation:
in an isosceles triangle, the hypotenuse equals a leg multiplied by [tex]\sqrt{2}[/tex]
what is the difference of -4-2 1/2?
Someone help need this to pass last question for today!
Answer: Reflection=simply flipping an object across a line without changing its size or shape. While Translation just slide a figure in any direction without changing its size, shape or orientation.
Hopes that helps have a blessing day/night :)
15–80÷4^2×2 as a expression using the order of operations.
[tex]\huge\text{Hey there!}[/tex]
[tex]\large\textsf{Do PEMDAS}[/tex]
[tex]\large\text{Parentheses}[/tex]
[tex]\large\text{Exponents}[/tex]
[tex]\large\text{Multiplication}[/tex]
[tex]\large\text{Division}[/tex]
[tex]\large\text{Addition}[/tex]
[tex]\large\text{Subtraction}[/tex]
[tex]\mathsf{15 - 80\div4^2\times2}[/tex]
[tex]\mathsf{4^2}[/tex]
[tex]\mathsf{= 4\times 4}[/tex]
[tex]\mathsf{= \bf 16}[/tex]
[tex]\mathsf{15 - 80\div16\times 2}[/tex]
[tex]\mathsf{80\div16}[/tex]
[tex]\mathsf{= \bf 5}[/tex]
[tex]\mathsf{15 - 5\times2 }[/tex]
5 × 2 = 10
[tex]\mathsf{15 - 10}[/tex]
[tex]\mathsf{= \bf 5}[/tex]
[tex]\boxed{\boxed{\large\textsf{Answer: \huge \bf 5}}}\huge\checkmark[/tex]
[tex]\text{Good luck on your assignment and enjoy your day!}[/tex]
~[tex]\frak{Amphitrite1040:)}[/tex]
If right I’ll mark brainiest need ASAP
Answer
Step-by-step explanation: Anybody who help me I will mark brainliest in give you 180 points you have to go on my page in answer all my questions
if 16c 1 gal then 1 1/4 gal __= c
Answer:
20 cups
Step-by-step explanation:
16 x 1.25 = 20
Answer:
11/4 c = 44 gal
I hope it's helps you
What is x plsssss help
Answer:
x = 6 (brainliest..?)
Step-by-step explanation:
x² = 4(4 + 5)
x² = 36
x = 6
Which phrase describes the shape of the data?
.
.
.
12
13
14
15
10
17
18
A. Symmetric, not bell-shaped
B. Not symmetric, bell-shaped
C. Not symmetric, not bell-shaped
D. Symmetric bell-shaped
Answer:
C. Not symmetric; not bell-shaped.
Step-by-step explanation:
In a symmetric data distribution, the shape on the left side is almost the same as the shape on the right side of the middle. In this type of data distribution, if different measure of centers are calculated (mean, median, and mode), they will have a similar figures that are close together. Symmetric distributions are bell-shaped.
On the other hand, if the data distribution is not symetric, it means the left and the right side of the distribution are not equal and do not have the same shape.
The data in the dot plot above is considered as NOT SYMMETRIC. Also, it is not bell-shaped.
Answer:
c
Step-by-step explanation:
Which equation gives the sum of...
S=0.2/1-8
S=1/8-0.2
S=8/0.2-1
S=8/1-0.2
Answer:
Option D
S=8/1-.2
Step-by-step explanation:
Edg
The sum of the sequence will be S = 8 / (1 – 0.2). Then the correct option is D.
What is the sum of the geometric series?Let a be the first term and r be the common ratio. Then the sum of the geometric series will be
S = a / (1 – r) if r < 1
S = a / (r – 1) if r > 1
The sum of [tex]\rm \Sigma_{n = 1}^{\infty} 8(0.2)^{n - 1}[/tex].
Then the first term of the geometric sequence will be 8.
And the common difference between the successive terms will be 0.2.
The common ratio less than one, then the formula for the sum will be given as
S = a / (1 – r) if r < 1
Then the sum of the sequence till infinity will be
S = 8 / (1 – 0.2)
S = 8 / 0.8
S = 10
Thus, the sum of the sequence will be S = 8 / (1 – 0.2).
Then the correct option is D.
More about the sum of the geometric series link is given below.
https://brainly.com/question/2771750
#SPJ5
which of the following could be the length of the side of a triangle
A :3,10 and 15
B :3,1 and 2
C :11,9, and 20
D :10,4, and 12