Answer:
12
Step-by-step explanation:
Basically you have to divide 3.14 by 452.16 (the formula for area of circle is pi times r squared) and that will get you 144. The square root of 144 is 12 :)
A survey sampled men and women workers and asked if they expected to get a raise or promotion this year. Suppose the survey sampled 200 men and 200 women. If 98 of the men replied Yes and 72 of the women replied Yes, are the results statistically significant so that you can conclude a greater proportion of men expect to get a raise or a promotion this year?
a. State the hypothesis test in terms of the population proportion of men and the population proportion of women.
b. What is the sample proportion for men? For women?
c. Use α= 0.01 level of significance. What is the p-value and what is your conclusion?
Answer:
a)
The null hypothesis is: [tex]H_0: p_M - p_W = 0[/tex]
The alternative hypothesis is: [tex]H_1: p_M - p_W > 0[/tex]
b) For men is of 0.49 and for women is of 0.36.
c) The p-value of the test is 0.0039 < 0.01, which means that the results are statistically significant so that you can conclude a greater proportion of men expect to get a raise or a promotion this year.
Step-by-step explanation:
Before solving this question, we need to understand the central limit theorem and subtraction of normal variables.
Central Limit Theorem
The Central Limit Theorem establishes that, for a normally distributed random variable X, with mean [tex]\mu[/tex] and standard deviation [tex]\sigma[/tex], the sampling distribution of the sample means with size n can be approximated to a normal distribution with mean [tex]\mu[/tex] and standard deviation [tex]s = \frac{\sigma}{\sqrt{n}}[/tex].
For a skewed variable, the Central Limit Theorem can also be applied, as long as n is at least 30.
For a proportion p in a sample of size n, the sampling distribution of the sample proportion will be approximately normal with mean [tex]\mu = p[/tex] and standard deviation [tex]s = \sqrt{\frac{p(1-p)}{n}}[/tex]
Subtraction between normal variables:
When two normal variables are subtracted, the mean is the difference of the means, while the standard deviation is the square root of the sum of the variances.
Men:
98 out of 200, so:
[tex]p_M = \frac{98}{200} = 0.49[/tex]
[tex]s_M = \sqrt{\frac{0.49*0.51}{200}} = 0.0353[/tex]
Women:
72 out of 200, so:
[tex]p_W = \frac{72}{200} = 0.36[/tex]
[tex]s_W = \sqrt{\frac{0.36*0.64}{200}} = 0.0339[/tex]
a. State the hypothesis test in terms of the population proportion of men and the population proportion of women.
At the null hypothesis, we test if the proportion are similar, that is, if the subtraction of the proportions is 0, so:
[tex]H_0: p_M - p_W = 0[/tex]
At the alternative hypothesis, we test if the proportion of men is greater, that is, the subtraction is greater than 0, so:
[tex]H_1: p_M - p_W > 0[/tex]
b. What is the sample proportion for men? For women?
For men is of 0.49 and for women is of 0.36.
c. Use α= 0.01 level of significance. What is the p-value and what is your conclusion?
From the sample, we have that:
[tex]X = p_M - p_W = 0.49 - 0.36 = 0.13[/tex]
[tex]s = \sqrt{s_M^2+s_W^2} = \sqrt{0.0353^2 + 0.0339^2} = 0.0489[/tex]
The test statistic is:
[tex]z = \frac{X - \mu}{s}[/tex]
In which X is the sample mean, [tex]\mu[/tex] is the value tested at the null hypothesis, and s is the standard error, so:
[tex]z = \frac{0.13 - 0}{0.0489}[/tex]
[tex]z = 2.66[/tex]
P-value of the test and decision:
The p-value of the test is the probability of finding a difference above 0.13, which is the p-value of z = 2.66.
Looking at the z-table, z = 2.66 has a p-value of 0.9961.
1 - 0.9961 = 0.0039.
The p-value of the test is 0.0039 < 0.01, which means that the results are statistically significant so that you can conclude a greater proportion of men expect to get a raise or a promotion this year.
Hi please somebody help me with this equation with explanation thank you
Answer:
[tex]{ \tt{ \frac{1}{24} m - \frac{2}{3} = \frac{3}{4} }} \\ \\ { \tt{ \frac{1}{24} m = \frac{17}{12} }} \\ m = 34[/tex]
Step 1: Find a common denominator
---The common denominator here is 24. So, we need to transform all of the fractions to have a denominator of 24.
1/24m - 16/24 = 18/24
Step 2: Solve
1/24m - 16/24 = 18/24
1/24m = 34/24
m = 34/24 x 24/1
m = 34
Hope this helps!
A survey is created to measure dietary habits. The survey asks questions about each meal and snack consumed for each day of the week. The survey seems like a good representation of measuring dietary habits. This survey would be considered to have high ______ validity.
Answer:
Face validity
Step-by-step explanation:
In quantitative research in mathematics, we have four major types of validity namely;
- Content Validity
- Construct validity
- Criterion validity
- Face validity.
Now;
> Construct validity seeks to find out if the tool used in measurement is a true representation of what is really going to be measured.
> Content Validity seeks to find out whether a test covers every part of a particular subject being tested.
> Face validity seeks to find out how true a test is by looking at it on the surface.
> Criterion validity seeks to find out the relationship of a particular test to that of another test.
Now, in this question, we are told that The survey seems like a good representation of measuring dietary habits after just asking questions about each meal and snack they consumed for the week. Thus, it is a face validity because it just appears true on the surface to be a good representation but we don't know if it is effective until we go deep like content validity
15. What is the solution to k+(-12) = 42? (1 point)
k=-54
k=-30
k= 30
k=54
Answer:
k = 54
Step-by-step explanation:
k + (-12) = 42
Remove parenthesis and addition sign
k - 12 = 42
Add 12 to both sides
K = 54
[tex]\boxed{\large{\bold{\textbf{\textsf{{\color{blue}{Answer}}}}}}:)}[/tex]
k+(-12)=42k-12=42k=42+12k=54Help me! Thanks! Show work too! Please!
Answer:
(2, 79) (12, 24)
24-79/12-2=-55/10
m=-0.55
24=-6,6+b
30.6=b
y=-0.55x+30.6
Step-by-step explanation:
you multiply
using the equation to represent your answer
HELP PLEASE BE CORRECT
Answer:
12
Step-by-step explanation:
Scale factor of 4
CD = 3
3 · 4 = 12
Length of C'D' is 12 units
Answer:
12 units
Step-by-step explanation:
The original segment CD = 3 units
Scale factor is 4.
3 x 4 = 12
The gross domestic product (GDP) of the United States is defined as
Answer:
the market value of all final goods and services produced within the United States in a given period of time.
A certain manufacturing process yields electrical fuses of which, in the long run
15% are defective. Find the probability that in a random sample of size n=10, fuses
selected from this process, there will be
(i) No defective fuse
(ii) At least one defective fuse
(iii) Exactly two defective fuses
(iv) At most one defective fuse
Answer:
i) 0.1969 = 19.69% probability that there will be no defective fuse.
ii) 0.8031 = 80.31% probability that there will be at least one defective fuse.
iii) 0.2759 = 27.59% probability that there will be exactly two defective fuses.
iv) 0.5443 = 54.43% probability that there will be at most one defective fuse.
Step-by-step explanation:
For each fuse, there are only two possible outcomes. Either it is defective, or it is not. The probability of a fuse being defective is independent of any other fuse, which means that the binomial probability distribution is used to solve this question.
Binomial probability distribution
The binomial probability is the probability of exactly x successes on n repeated trials, and X can only have two outcomes.
[tex]P(X = x) = C_{n,x}.p^{x}.(1-p)^{n-x}[/tex]
In which [tex]C_{n,x}[/tex] is the number of different combinations of x objects from a set of n elements, given by the following formula.
[tex]C_{n,x} = \frac{n!}{x!(n-x)!}[/tex]
And p is the probability of X happening.
15% are defective.
This means that [tex]p = 0.15[/tex]
We also have:
[tex]n = 10[/tex]
(i) No defective fuse
This is [tex]P(X = 0)[/tex]. So
[tex]P(X = x) = C_{n,x}.p^{x}.(1-p)^{n-x}[/tex]
[tex]P(X = 0) = C_{10,0}.(0.15)^{0}.(0.85)^{10} = 0.1969[/tex]
0.1969 = 19.69% probability that there will be no defective fuse.
(ii) At least one defective fuse
[tex]P(X \geq 1) = 1 - P(X = 0)[/tex]
We already have P(X = 0) = 0.1969, so:
[tex]P(X \geq 1) = 1 - 0.1969 = 0.8031[/tex]
0.8031 = 80.31% probability that there will be at least one defective fuse.
(iii) Exactly two defective fuses
This is P(X = 2). So
[tex]P(X = x) = C_{n,x}.p^{x}.(1-p)^{n-x}[/tex]
[tex]P(X = 2) = C_{10,2}.(0.15)^{2}.(0.85)^{8} = 0.2759[/tex]
0.2759 = 27.59% probability that there will be exactly two defective fuses.
(iv) At most one defective fuse
This is:
[tex]P(X \leq 1) = P(X = 0) + P(X = 1)[/tex]. So
[tex]P(X = x) = C_{n,x}.p^{x}.(1-p)^{n-x}[/tex]
[tex]P(X = 0) = C_{10,0}.(0.15)^{0}.(0.85)^{10} = 0.1969[/tex]
[tex]P(X = 1) = C_{10,1}.(0.15)^{1}.(0.85)^{9} = 0.3474[/tex]
Then
[tex]P(X \leq 1) = P(X = 0) + P(X = 1) = 0.1969 + 0.3474 = 0.5443[/tex]
0.5443 = 54.43% probability that there will be at most one defective fuse.
URGENT!!!!!! 15 POINTDS
Answer:
Option C
Step-by-step explanation:
thankful that there are graphing tools. see screenshot
Use the figure to find y.
Tanθ =sin /cos
tan θ = 5/2 / y
tan (30°) = 5/2 /y
[tex]y = \frac{5 \sqrt{3} }{2} [/tex]
y=4.33
Domain and range problem Help
Answer:
Range y≤-1
Domain all reals
Step-by-step explanation:
The range is the output values (y)
Y is less than or equal to -1
y≤-1
The domain is the values that the input can take
the arrows on the ends of the graph tells us x can take all real numbers
The range is the span of y-values. What is the smallest possible y-value and what is the largest possible y-value?
For this problem, the y-values start at -1 and decrease infinitely. Therefore, the range is y <= -1.
The domain is the span of x-values. What is the smallest possible x-value and what is the largest possible x-value?
For this problem, the parabola will keep expanding horizontally (or to the left and right). Therefore, the range is all real numbers.
Hope this helps!
Complete the input-output table:
x 3x + 7
0
4
8
14
Step-by-step explanation:
When x = 0,
3x + 7
= 3 ( 0 ) + 7
= 0 + 7
= 7
When x = 4,
3x + 7
= 3 ( 4 ) + 7
= 12 + 7
= 19
When x = 8,
3x + 7
= 3 ( 8 ) + 7
= 24 + 7
= 31
When x = 14,
3x + 14
= 3 ( 14 ) + 14
= 14 ( 3 + 1 )
= 14 ( 4 )
= 56
what's a divisor a dividend and a quotient
a plane can fly 450 miles in the same time it takes a car to go 150 miles. if the car travels 100 mph slower than the plane, find the speed (in mph) of the plane
Answer:
The speed of the plane is 150 miles per hour, while the speed of the car is 50 miles per hour.
Step-by-step explanation:
Since a plane can fly 450 miles in the same time it takes a car to go 150 miles, if the car travels 100 mph slower than the plane, to find the speed (in mph) of the plane the following calculation must be performed:
450 to 150 is equal to 3: 1, that is, the plane travels three times the distance of the car.
Therefore, since 100/2 x 3 equals 150, the speed of the plane is 150 miles per hour, while the speed of the car is 50 miles per hour.
If f(x) = x
2−3x+1
x−1
find f(-1) and f(-3)
Answer:
f(-1) = 2-3(-1) +1
= 7
f(-3)= 2-3(-3)+1
= 12
f(-1) = -1-1
= -2
f(-3) = -3-1
= -4
a.
What is 46.7% of
4/5?
Answer:
0.3736
Step-by-step explanation:
46.7 percent of [tex]\frac{4}{5}[/tex] is 0.3736.
What is the percentage?A percentage is a figure or ratio stated as a fraction of 100 in mathematics. Although the abbreviations "pct," "pct," and occasionally "pc" are also used, the percent sign, " percent ", is frequently used to signify it. A % is a number without dimensions and without a standard measurement.What is a fraction?A number is stated as a quotient in mathematics when the numerator and denominator are divided. Both are integers in a simple fraction. A fraction appears in the numerator or denominator of a complex fraction. The numerator of a proper fraction is less than the denominator.Solution -To find 46.7% of [tex]\frac{4}{5}[/tex].
So,
[tex]\frac{46.7}{100}[/tex] × [tex]\frac{4}{5}[/tex]
[tex]\frac{0.467}{100}[/tex] × [tex]\frac{4}{5}[/tex]
⇒ [tex]0.3736[/tex]
Therefore, 46.7% of [tex]\frac{4}{5}[/tex] is 0.3736.
Know more about percentages here:
https://brainly.com/question/24304697
#SPJ2
Which equation represents the parabola with focus (8, 4) and vertex (8, 2)
Answer:
Step-by-step explanation:
The focus lies above the vertex, so the parabola opens upwards.
The diameter of the circle is 2”. What is the area of the circle
Answer:
[tex]\pi[/tex]
Step-by-step explanation:
1. 2/2 =1 1 is the radius
2. [tex]A = \pi r^2[/tex]
3. [tex]A=\pi 1^2[/tex]
4. [tex]A=\pi[/tex]
Determine if the sequence below is arithmetic or
geometric and determine the common difference / ratio in
simplest form.
3, 8, 13, ..
(PLEASE HELPP)
9514 1404 393
Answer:
arithmetic; common difference of 5
Step-by-step explanation:
It usually works well to check differences first. Here, they are ...
8 -3 = 5
13 -8 = 5
These are the same value, so the sequence is arithmetic with a common difference of 5.
What is the value of x?
Answer:
Step-by-step explanation:
(2x - 5)° + 45° = 180°
2x - 5 + 45 = 180
x = 70
Find mBFE, help ASAP!!!
Answer: C
<BFE is 148 degrees
Step-by-step explanation:
We have angles <BFC (57 degrees) and <CFD (34 degrees), but what is <DFE?
1. The angle symbol in the vertexes shows that <BFC is congruent to <DFE, meaning that they are the same
2. Knowing this, we can safely say that <DFE is equal to 57 degrees because <BFC is also 57 degrees.
3. Now, we have all the angles we need to find out <BFE.
4. <BFC+<CFD+<DFE=<BFE
5. Substitute to get
57+34+57=<BFE
91+57=<BFE
148=<BFE
6. Now we know that the answer is 148 degrees.
Ming rented a bike from Ted's Bikes. It cost $13 plus $3 per hour. If Ming paid $31,
then he rented the bike for how many hours?
A)7.
B)10.3333
C)6
D)10
Answer:
C, 6
Step-by-step explanation:
31-13 is 18, 18/3 is 6.
Answer:
6
Step-by-step explanation:
31-13= 18
18÷3 = 6
Answer from Gauthmath
Peter, Jan, and Maxim are classmates. Their total score for the last test was 269. Peter's score was more than the sum of Jan's and Maxim's scores. What could be Peter's least possible score?
Answer:
135
Step-by-step explanation:
Given that :
Total score obtained by Peter, Jan and Maxim = 269
Let :
Peter's score = x
Jan's score = y
Maxim's score = z
x + y + z = 269
x > (y + z)
For x to be greater Than y + z ;
Then x > (269 / 2) ; x > 134.5
The least possible x score is 135
Hence, Peter's least possible score is 135.
What is the index of the radical below?
√10
A. 5
B. 9
C. 2
D. 10
16. write an inequality for each graph
a.....
b.....
17. Graph each inequality on a number line.
a.....
b....
Answer:
Question 16
(a) x < 1 : the values of x are smaller than than 1 (e.g. possible values are 0, -1, -2, etc) and since the circle is not shaded it means that 1 isn't a possible value of x
(b) x [tex]\geq[/tex] -2 : the circle is filled therefore -2 is included in the answer
Question 17
(a) unfilled dot above -2 and arrow pointing to the left
(b) shaded circle above 4 with and arrow pointing to the right →
Martha ran a 3-mile race in 24 minutes. how long does it take her to run 1 mile?
Answer:
8 minuets
Step-by-step explanation:
24min/3miles = 8
Answer:
8 minutes.
Step-by-step explanation:
If we divide 24 minutes by 3 miles, your answer will be 8 minutes.
A town recently dismissed 10 employees in order to meet their new budget reductions. The town had 7 employees over 50 years of age and 18 under 50. If the dismissed employees were selected at random, what is the probability that exactly 5 employees were over 50
Answer:
0.055 = 5.5% probability that exactly 5 employees were over 50.
Step-by-step explanation:
The employees are dismissed from the sample without replacement, which means that the hypergeometric distribution is used to solve this question.
Hypergeometric distribution:
The probability of x successes is given by the following formula:
[tex]P(X = x) = h(x,N,n,k) = \frac{C_{k,x}*C_{N-k,n-x}}{C_{N,n}}[/tex]
In which:
x is the number of successes.
N is the size of the population.
n is the size of the sample.
k is the total number of desired outcomes.
Combinations formula:
[tex]C_{n,x}[/tex] is the number of different combinations of x objects from a set of n elements, given by the following formula.
[tex]C_{n,x} = \frac{n!}{x!(n-x)!}[/tex]
In this question:
Total of 7 + 18 = 25 employees, which means that [tex]N = 25[/tex]
7 over 50, which means that [tex]k = 7[/tex]
10 were dismissed, which means that [tex]n = 10[/tex]
What is the probability that exactly 5 employees were over 50?
This is P(X = 5). So
[tex]P(X = x) = h(x,N,n,k) = \frac{C_{k,x}*C_{N-k,n-x}}{C_{N,n}}[/tex]
[tex]P(X = 5) = h(5,25,10,7) = \frac{C_{7,5}*C_{18,5}}{C_{25,10}} = 0.055[/tex]
0.055 = 5.5% probability that exactly 5 employees were over 50.
❤✔
PLEASE HELP ME MAKE SURE YOUR ANSWER IS RIGHT BEFORE ANSWERING
Answer:
Always. Always.
Step-by-step explanation:
All circles conform to the same equations such as using pie to calculate circumference. Unlike a rectangle, for example, all ratios used in a circle are the same.
Find the equation of line b in slope-intercept form. Line a is parallel to line b. Line a passes through the points (1,8) and (2,-1), line b passes through the point (4,13)
9514 1404 393
Answer:
y = -9x +49
Step-by-step explanation:
The slope of line b is the same as the slope of line a. That can be found using the slope formula:
m = (y2 -y1)/(x2 -x1)
m = (-1 -8)/(2 -1) = -9
The y-intercept can be found from the given point using the formula ...
b = y - mx
b = 13 -(-9)(4) = 13 +36 = 49
Then the slope-intercept equation of line b is ...
y = -9x +49
Find the interest on the loan using the Banker's rule. P= $8550. r=8.8%, t= 105 days The interest on the loan using the Banker's rule is $
