Answer: 15
Step-by-step explanation: r=V
πh=10597.5
π·15≈14.9962
In hypothesis testing, the null hypothesis is the hypothesis that the researcher believes is true and wishes to prove. True or False
Answer:true
Step-by-step explanation:
A student researcher compares the ages of cars owned by students and cars owned by faculty at a local state college. A sample of 138 cars owned by students had an average age of 5.13 years. A sample of 111 cars owned by faculty had an average age of 7.75 years. Assume that the population standard deviation for cars owned by students is 3.45 years, while the population standard deviation for cars owned by faculty is 2.08 years. Determine the 95% confidence interval for the difference between the true mean ages for cars owned by students and faculty. Step 1 of 3: Find the point estimate for the true difference between the population means.
Answer:
The point estimate for the true difference between the population means is of -2.62 years.
The 95% confidence interval for the difference between the true mean ages for cars owned by students and faculty is between -3.4 years and -1.84 years.
Step-by-step explanation:
Before building the confidence interval, we need to understand the central limit theorem, and subtraction between normal variables.
Central Limit Theorem
The Central Limit Theorem estabilishes 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 of normal variables:
When we subtract normal variables, the mean is the subtraction of the mean, while the standard deviation is the square root of the sum of variances.
A sample of 138 cars owned by students had an average age of 5.13 years. The population standard deviation for cars owned by students is 3.45 years.
This means that:
[tex]\mu_{s} = 5.13, \sigma_{s} = 3.45, n = 138, s_s = \frac{3.45}{\sqrt{138}} = 0.2937[/tex]
A sample of 111 cars owned by faculty had an average age of 7.75 years. The population standard deviation for cars owned by faculty is 2.08 years.
This means that [tex]\mu_{f} = 7.75, \sigma_{f} = 2.08, n = 111, s_f = \frac{2.08}{\sqrt{111}} = 0.2658[/tex]
Difference between the true mean ages for cars owned by students and faculty.
s - f
Mean:
[tex]\mu = \mu_s - \mu_f = 5.13 - 7.75 = -2.62[/tex]
This is the point estimate for the true difference between the population means.
Standard deviation:
[tex]s = \sqrt{s_s^2+s_f^2} = \sqrt{0.2937^2+0.2658^2} = 0.3961[/tex]
Confidence interval:
We have that 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 Ztable as such z has a pvalue of [tex]1 - \alpha[/tex].
That is z with a pvalue of [tex]1 - 0.025 = 0.975[/tex], so Z = 1.96.
Now, find the margin of error M as such
[tex]M = zs = 1.96*0.3961 = 0.78[/tex]
The lower end of the interval is the sample mean subtracted by M. So it is -2.62 - 0.78 = -3.4
The upper end of the interval is the sample mean added to M. So it is -2.62 + 0.78 = -1.84
The 95% confidence interval for the difference between the true mean ages for cars owned by students and faculty is between -3.4 years and -1.84 years.
The Thompson family is buying a car that can travel 70 miles
Answer:
The car gets 35 miles per gallons.
Step-by-step explanation:
1/3x + 2 =4 I need it ASAP
Answer:
x=1/6 or 0.16
Step-by-step explanation:
x has to be whatever makes the equation true.
does 1/3 +2= 4 alone no does it = 4 when you do the 1/3(1/6) yes
What fraction of 2 minutes is 6
seconds?
Answer:
1/20 of 2 minutes = 6 seconds
Answer:
1/20; 0.05; 5%
Step-by-step explanation:
Well, 2 minutes is 120 seconds, 6/120 simplified is 1/20, and decimal form would be 0.05, which is 5%
How to figure out square feet of counter tops
Answer:
Chapter Three: Calculate Total Countertop Square Footage
To calculate the total square footage (after placing seams) you will need to follow this formula: “L” x “W” / 144 = s.f. (Length times width divided by 144 = square feet).
What is the tangent ratio of angle within a right triangle?
9514 1404 393
Answer:
(d)
Step-by-step explanation:
The purpose of the mnemonic SOH CAH TOA is to help you remember that ...
Tan = Opposite/Adjacent
A survey found that 20% of the people in Fiji drive the car without seatbelt. If 3 people are randomly selected, find the probability that at least 2 drive without seat.
Answer:
0.104 = 10.4% probability that at least 2 drive without a seatbelt.
Step-by-step explanation:
For each person, there are only two possible outcomes. Either they drive without a seatbelt, or they do not. The probability of a person driving without a seatbelt is independent of any other person. This means that we use the binomial probability distribution 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.
20% of the people in Fiji drive the car without seatbelt.
This means that [tex]p = 0.2[/tex]
3 people are randomly selected
This means that [tex]n = 3[/tex]
Find the probability that at least 2 drive without a seatbelt?
This is:
[tex]P(X \geq 2) = P(X = 2) + P(X = 3)[/tex]
In which
[tex]P(X = x) = C_{n,x}.p^{x}.(1-p)^{n-x}[/tex]
[tex]P(X = 2) = C_{3,2}.(0.2)^{2}.(0.8)^{1} = 0.096[/tex]
[tex]P(X = 3) = C_{3,3}.(0.2)^{3}.(0.8)^{0} = 0.008[/tex]
[tex]P(X \geq 2) = P(X = 2) + P(X = 3) = 0.096 + 0.008 = 0.104[/tex]
0.104 = 10.4% probability that at least 2 drive without a seatbelt.
Question 20(Multiple Choice Worth 2 points) (01.02 LC) Which number has a 9 that is one tenth the value of the 9 in 296? 195 409 981 1,956 NO LINKS HELP ASAP
Answer:
409 i would say
Step-by-step explanation:
very sorry is its wrong!!! :(
Answer:
prob d im guessing :^)
Step-by-step explanation:
tell me if i got it right or wrong i will fix if needed
Find f. (Use C for the constant of the first antiderivative and D for the constant of the second antiderivative.) f ''(x) = 2x + 5ex
Answer:
Step-by-step explanation:
f ''(x) = 2x + 5e^x
f '(x) = x² + 5e^x + D
f (x) = 1/3 x³ + 5e^x + C
Complete the sentence.
9 is 36% of
Answer:
3.24
Step-by-step explanation:
9 takes up 3.24 of 36%
Answer:
9 is 36% of 25
Step-by-step explanation:
36%×x=9
36/100×x=9
x=9×100/36
x=25
Solve the system of equations by graphing. Look at the picture. Will Mark Brainliest
Answer:
See below
Step-by-step explanation:
Graphing:we are given two functions
[tex] \displaystyle \begin{cases}f(x) = - x + 5 \\ g(x) = {x}^{2} - 3x + 2\end{cases}[/tex]
where f(x) is a linear function and g(x) is a quadratic function
we want to figure out the solutions of the function
let's graph f(x):
the Black-table is attached
let's graph g(x):
the picture is attached
hence, the graph should be
the graph is attached
solutions stating:so we need solution(s) which satisfy(ies) the both functions
in this case the solution (s) the x coordinate(s) where both functions intercept we get from the graph that both functions intercept at (-1,6) and (3,2)
hence,
x={-1,3}
ASAP
a golden bar has a mass of 12.5kg. the density of gold is 19.3 g/cm^3. work out the volume of the gold bar. give your answer to correct 3 sf.
Answer:
647.668 cm³
Step-by-step explanation:
12.5 kg = 12500 g
12500 g/19.3 g/cm³ = 647.668 cm³
5/6 plus blank equals to 5/2
Answer:
[tex]\frac{5}{3}[/tex]
Step-by-step explanation:
let blank be O
[tex]\frac{5}{6} +O=\frac{5}{2} \\[/tex]
[tex]O=\frac{5}{2} -\frac{5}{6} =\frac{15}{6} -\frac{5}{6} =\frac{10}{6} =\frac{5}{3}[/tex]
2. Which of the following is considered an
asset?
A Savings account
B Credit card debt
C Personal loan
D Mortgage
Answer:
A
Step-by-step explanation:
All of the rest you have to pay off. A savings account is a good place to keep money safe for the future, and you can also make interest.
1. What is the median of the following numbers? 36,42,28, 52, 48, 36, 31
36
O 42
O 48
To solve the equation 5sin(2x)=3cosx, you should rewrite it as___.
Answer:
A
Step-by-step explanation:
We want to solve the equation:
[tex]5\sin(2x)=3\cos(x)[/tex]
To do so, we can rewrite the equation.
Recall the double-angle identity for sine:
[tex]\sin(2x)=2\sin(x)\cos(x)[/tex]
By substitution:
[tex]5\left(2\sin(x)\cos(x)\right)=3\cos(x)[/tex]
Distribute:
[tex]10\sin(x)\cos(x)=3\cos(x)[/tex]
We can subtract 3cos(x) from both sides:
[tex]10\sin(x)\cos(x)-3\cos(x)=0[/tex]
And factor:
[tex]\cos(x)\left(10\sin(x)-3\right)=0[/tex]
Hence, our answer is A.
*It is important to note that we should not divide both sides by cos(x) to acquire 10sin(x) = 3. This is because we need to find the values of x, and one or more may result in cos(x) = 0 and we cannot divide by 0. Hence, we should subtract and then factor.
Answer:
A. cosx(10sinx-3)=0
Step-by-step explanation:
5(2sinxcosx)=3cosx
10sinxcosx-3cosx=0
cosx(10sinx-3)=0
NEED ANSWER ASAP,BRAINLIEST FOR CORRECT ANSWER. IM FAILING SCHOOL
Answer:
angle b= 86 degrees
Step-by-step explanation:
hope this helps, have a nice day :)
Ceasar opens a bank account and makes an initial deposit of $800. The banker tells Ceasar that he is going to receive an annual rate of 10% compounded continuously on his investment. Find the bank balance assuming Ceasar leaves the account untouched for 8 years.
Can you please do the problem using the formula A(t)=pe^(rt).
Answer:
1780.43
Step-by-step explanation:
Given:
P = 800
r = 10% or 0.1
t = 8
Work:
[tex]A=Pe^{rt}\\\\A=800e^{0.1*8}\\\\A=800e^{0.8}\\\\A=1780.43[/tex]
I need help with this i cant cuaet understand it.
Answer:
Seattle is more likely to have rain.
Step-by-step explanation:
Seattle has a 75% chance of rain
Tacoma has a 1/4 chance of rain.
100% = 4/4
75% = 3/4
50% = 2/4
25% = 1/4
25% < 75%
Answer:
Step-by-step explanation:
The graph of g is a translation 3 units up, followed by a reflection in the x-axis of the graph of
f(x) = 2 sin x. Which rule represents g?
Answer: NO GRAPH DUMMY
Step-by-step explanation:
Solve for x if 5^x=200
Answer:
x ≈ 3.29
Step-by-step explanation:
Take the logarithm of both sides of the equation to remove the variable from the exponent.
Exact Form:
x = [tex]\frac{ln(200)}{ln(5)}[/tex]
Decimal Form:
x = 3.29202967 … ≈ 3.29 (Round to what the question asks, in this case, I rounded to 2 decimal places)
Answer:
ln200/ln5
Step-by-step explanation:
ln5^x=ln200
xln5=ln200
x=ln200/ln5
the volume of a rectangle prism is 8cm height 4 width.
Answer:
Step-by-step explanation:
Question 5.... plz help
Answer:
ANSWER : 4
Step-by-step explanation:
hello :
tanA=7/2 means : A= tan^-1 (7/2) =74°
Find the value of x in the parallelogram below.
Answer:
B) x = 12
Step-by-step explanation:
m∡EOU = m∡TQE
m∡EOU =180 - (39+45) = 96°
m∡TQE: 7x + 12 = 96
7x = 84
x = 12
Can u please help me ? I will mark you brainliest
Answer:
I believe it's the 4th one the 2nd on the right under that the one i think is selected looks right!
Answer is 4th one.
Step-by-step explanation:
Hope i helped! Your welcome! Have a great week!
a seventh grade special education classroom consists of 14 girls and 16 boys. If 10 of the students are selected at random to help a fourth grade math class, determine the probability that all boys will be selected.
Answer:
8/30015 or .037%
Step-by-step explanation:
16/30 × 15/29 × 14/28 × 13/27 × 12/26 x 11/25 x 10/24 × 9/23 × 8/22 × 7/21
= 8/30015
Please help I’ll mark you as brainliest if correct!
Answer:
B
Step-by-step explanation:
brainliest?
please help
Find the missing side of this right
triangle.
21
х
15
X =
= V[?]
Answer:
216
Step-by-step explanation:
^
factoring review 2 terms 1-8
Answer:
ok
Step-by-step explanation:
whats the question?