Someone claims that the breaking strength of their climbing rope is 2,000 psi, with a standard deviation of 10 psi. We think the actual amount is lower than that and want to run the test at an alpha level of 5%. What would our sample size need to be if we want to reject the null hypothesis if the sample mean is at or below 1,997.2956?
Answer:
The sample size must be greater than 37 if we want to reject the null hypothesis.
Step-by-step explanation:
We are given that someone claims that the breaking strength of their climbing rope is 2,000 psi, with a standard deviation of 10 psi.
Also, we are given a level of significance of 5%.
Let [tex]\mu[/tex] = mean breaking strength of their climbing rope
SO, Null Hypothesis, [tex]H_0[/tex] : [tex]\mu[/tex] = 2,000 psi {means that the mean breaking strength of their climbing rope is 2,000 psi}
Alternate Hypothesis, [tex]H_A[/tex] : [tex]\mu[/tex] < 2,000 psi {means that the mean breaking strength of their climbing rope is lower than 2,000 psi}
Now, the test statistics that we will use here is One-sample z-test statistics as we know about population standard deviation;
T.S. = [tex]\frac{\bar X-\mu}{\frac{\sigma}{\sqrt{n} } }[/tex] ~ N(0,1)
where, [tex]\bar X[/tex] = ample mean strength = 1,997.2956 psi
[tex]\sigma[/tex] = population standard devaition = 10 psi
n = sample size
Now, at the 5% level of significance, the z table gives a critical value of -1.645 for the left-tailed test.
So, to reject our null hypothesis our test statistics must be less than -1.645 as only then we have sufficient evidence to reject our null hypothesis.
SO, T.S. < -1.645 {then reject null hypothesis}
[tex]\frac{\bar X-\mu}{\frac{\sigma}{\sqrt{n} } } < -1.645[/tex]
[tex]\frac{1,997.2956-2,000}{\frac{10}{\sqrt{n} } } < -1.645[/tex]
[tex](\frac{1,997.2956-2,000}{10}) \times {\sqrt{n} } } < -1.645[/tex]
[tex]-0.27044 \times \sqrt{n}< -1.645[/tex]
[tex]\sqrt{n}> \frac{-1.645}{-0.27044}[/tex]
[tex]\sqrt{n}>6.083[/tex]
n > 36.99 ≈ 37.
SO, the sample size must be greater than 37 if we want to reject the null hypothesis.
A rocket moves through outer space at 10,500 m/s. At this rate how much time would be required to travel the distance from Earth to the moon, which is 380,000 km?
Answer:
The answer is around 27.63 seconds.
Step-by-step explanation:
1 km equals 1000 meters so we have to multiply 10,500 and 1,000 which would equal 10,500,000 km. 10,500,000 divided by 380,000 which is around 27.63 seconds.
The notation f:S→T denotes that f is a function, also called a map , defined on all of a set S and whose outputs lie in a set T . A function f:S→T is injective if for all x,y∈S , f(x)=f(y) implies that x=y . Alternatively: a function is injective if we can uniquely recover some input x based on an output f(x) . What functions are injective?
Answer:
There are many. Two examples are
[tex]f(x) = x, \\f(x) = x^3[/tex]
Step-by-step explanation:
There are many examples. The simplest is
1 -
[tex]f(x) = x[/tex]
It is trivial that
[tex]\text{if \,\,\,\,} f(x) = f(y) \,\,\,\,\,\text{then} \,\,\,\,\, x=y[/tex]
2 -
[tex]f(x) = x^3[/tex]
That function is injective as well.
[tex]\text{if \,\,\,\,} x^3 = y^3 \,\,\,\,\,\text{then} \,\,\,\,\, x=y[/tex]
An example of a function that is NOT injective is
[tex]f(x) = x^2[/tex]
Notice that
[tex]f(-2) = (-2)^2 = 2^2 = 4[/tex]
Suppose 90 geology students measure the mass of an ore sample. Due to human error and limitations in the reliability of the​ balance, not all the readings are equal. The results are found to closely approximate a normal​ curve, with mean 88 g and standard deviation 1 g. Use the symmetry of the normal curve and the empirical rule as needed to estimate the number of students reporting readings between 87 g and 89 g.The number of students reporting readings between 87 g and 89 g is:________
Answer:
The number of students reporting readings between 87 g and 89 g is 61
Step-by-step explanation:
The Empirical Rule states that, for a normally distributed random variable:
68% of the measures are within 1 standard deviation of the mean.
95% of the measures are within 2 standard deviation of the mean.
99.7% of the measures are within 3 standard deviations of the mean.
In this problem, we have that:
Mean = 88g
Standard deviation = 1g
Percentage of students reporting readings between 87 g and 89 g
87 = 88-1
So 87 is one standard deviation below the mean.
89 = 88+1
So 89 is one standard deviation above the mean.
By the Empirical Rule, 68% of students are reporting readings between 87 g and 89 g.
Out of 90 students:
0.68*90 = 61.2
Rounding to the nearest whole number:
The number of students reporting readings between 87 g and 89 g is 61
I NEED AN ANSWER IN MINUTES!!! WILL GIVE BRAINLIEST!!!!
Examine the diagram.
2 lines intersect a horizontal line to form 3 angles. The angles are 1, 90 degrees, 2.
Which statement is true about angles 1 and 2?
Angles 1 and 2 are complementary.
Angles 1 and 2 are vertical.
Angles 1 and 2 are supplementary.
Angles 1 and 2 are adjacent.
Answer:
I think that angles 1 and 2 are complementary
Step-by-step explanation:
option 1
plz mark brainliest!
Answer:a
Step-by-step explanation:
(a) Use a linear approximation to estimate f(0.9) and f(1.1). f(0.9) ≈ f(1.1) ≈ (b) Are your estimates in part (a) too large or too small? Explain. The slopes of the tangent lines are negative, but the tangents are becoming steeper. So the tangent lines lie below the curve f. Thus, the estimates are too large. The slopes of the tangent lines are negative, but the tangents are becoming steeper. So the tangent lines lie below the curve f. Thus, the estimates are too small. The slopes of the tangent lines are positive, but the tangents are becoming less steep. So the tangent lines lie above the curve f. Thus, the estimates are too large. The slopes of the tangent lines are positive, but the tangents are becoming less steep. So the tangent lines lie above the curve f. Thus, the estimates are too small.
Answer:
(Missing part of the question is attached)
[tex]L(x)=2x+3[/tex]
Estimates are too large.
Step-by-step explanation:
Suppose the only information we know about the function is:
[tex]f(1)=5[/tex]
where the graph of its derivative is shown in the attachment
(a)If the function [tex]f\\[/tex] is differentiable at point [tex]x=1[/tex] , the tangent line to the graph of [tex]f[/tex] at 1 is given by the equation:
[tex]y=f(1) +f'(1)(x-1)[/tex]
So we call the linear function:
[tex]L(x)=f(1) +f'(1)(x-1)[/tex]
We know the [tex]f(1)=5[/tex] as it is given in the question, and [tex]f'(1)=2[/tex] from the graph attached. Substitute in the equation of [tex]L(x)[/tex].
[tex]L(x)=5+2(x-1)\\L(x)=5+2x-2\\L(x)=2x+3\\[/tex]
(b)At x=1, [tex]f'(x)[/tex] is positive but it is decreasing. However. if we draw the tangent lines, we see that the tangent lines are becoming less steeper, so the tangent lines lie above the curve [tex]f[/tex]. Thus, The estimates are too large.
Assume that the heights of men are normally distributed with a mean of 70.9 inches and a standard deviation of 2.1 inches. If 36 men are randomly selected, find the probability that they have a mean height greater than 71.9 inches. Round to four decimal places.
Answer:
The probability that they have a mean height greater than 71.9 inches
P( x⁻ ≥71.9) = 0.0022
Step-by-step explanation:
Explanation:-
Given mean of the Population μ= 70.9
Standard deviation of the Populationσ = 2.1
Given sample size 'n' =36
let x⁻ be the mean height
given x⁻ =71.9 inches
[tex]Z=\frac{x^{-} -mean}{\frac{S.D}{\sqrt{n} } }[/tex]
[tex]Z=\frac{71.9 -70.9}{\frac{2.1}{\sqrt{36} } } = \frac{1}{0.35} = 2.85[/tex]
The probability that they have a mean height greater than 71.9 inches
P( x⁻ ≥71.9) = P(Z ≥ 2.85)
= 1 - P(Z≤ 2.85)
= 1 - ( 0.5 + A(2.85)
= 0.5 - A( 2.85)
= 0.5 - 0.4978
= 0.0022
The probability that they have a mean height greater than 71.9 inches
P( x⁻ ≥71.9) = 0.0022
Answer:
the answer is 0.0022
Step-by-step explanation:
A
B
C
D
Help me out
Answer:
2x^2 + 3/2x -5
Step-by-step explanation:
f(x) = x/2 -2
g(x) = 2x^2 +x -3
f(x)+ g(x) = x/2 -2+ 2x^2 +x -3
Combine like terms
= 2x^2 + 3/2x -5
After a series of major corporations admitted to large accounting irregularities, a public policy research institute conducts a survey to determine whether the public favors increased governmental regulation and oversight of corporations. Which of the following questions will deliver an unbiased response?
a. In light of the recent wave of shocking corporate accounting fraud, should government increase its regulation and oversight of corporations?
b. Should privately-owned companies be subjected to intrusive governmental regulation and oversight?
c. ls the government doing enough to protect American shareholders from corporate greed?
d. None of the above
Answer:
I think option B
Step-by-step explanation:
Should privately-owned companies be subjected to intrusive governmental regulation and oversight?
This question will produce an unbiased answer either a yes or a no. The question is simple and not too loaded and it is direct without including an inclination to bend to a particular direction. It will produce unbiased responses in that no comment was made about the admittance to large accounting irregularities.
8b-ab=7a, .subtracted from 3a-9ab+b
Answer: You can't. Read explanation.
Step-by-step explanation:
You can't subtract an expression from an equation. If you said something like subtract 8b-ab+7a from 3a-9ab+b that would work, but not here.
Let's just assume You mean it as 8b-ab-7a, then (3a-9ab+b)-(8b-ab-7a) = -8ab + 10a - 7b.
Hope that helped,
-sirswagger21
question is attached
I apologize, I am stumped... I thought you would find either the centroid, circumcenter, or incenter of the triangle created but it didn't work quite right for me.
Mary wants to fill in a cylinder vase. At the flower store they told her that the vase should be filled for the flowers to last the longest. Her cylinder vase has a radius of 2 in and a height of 9 in. How much water should Mary pour into the vase?
please help
Answer:
113.09 hope this helps
Step-by-step explanation:
13. Carla drew two acute non-overlapping
angles that share a ray and labeled them
ZJLK and Z KLM. The two angles have
different measures. Carla says
ZILM is
greater than a right angle.
An acute angle is open
less than a right angle.
Answer:
An acute angle is open
Step-by-step explanation:
An acute angle is an angle that is less than [tex]90^{0}[/tex]. Two or more acute angles are set to be complementary if their sum equals a right angle.
Clara's diagram involves two acute angles JLK and KLM with both sharing the side LK.
If the acute angles are complementary angles, then JLM would be a right angle.
If the acute angles are not complementary angles, then JLM would be less than a right angle.
So the appropriate choice to select is an acute angle is open. Which implies that JLM may be a right angle or not depending on the degrees of the acute angles involved.
Which of the following statements is NOT true?
YA
The slope of AB is
different than the
slope of BC.
The ratios of the rise to
the run for the triangles
are equivalent.
B
2.
х
-2
AB has the same slope
as AC.
The slope of Ac is
Answer:
The slope of AB is
different than the
slope of BC.
Step-by-step explanation:
Please answer this question I give brainliest thank you! Number 9
Answer:
B
The mode is 11 and 3
The Median is 10
The mean is 12
Mo has some red and green sweets He eats 1/3 of the sweets ¾ of the sweets left over are green Mo buys himself 30 more green sweets. There are now 162 green sweets. How many sweets did Mo start with?
Answer:
176 sweets
Step-by-step explanation:
162 - 30 = 132 this finds the 3/4 before he purchased more sweets.
132 divided by 3 = 44 This finds how many thirds their are. (We do 3 not 4 because 1/4 is already gone and there are only 3rds lefts.)
44 x 4 = 176 This finds the total before he purchased more.
Hope this helps!
I don’t know if it’s g(2(5)(3(5)^2-5-5
Answer:
B. 135
Step-by-step explanation:
For ...
f(x) = 3x^2 -xg(x) = 2x -5f(5) = 3·5^2 -5
= 3·25 -5 = 75 -5 = 70
Then g(f(5)) is ...
g(f(5)) = g(70) = 2·70 -5 = 140 -5
g(f(5)) = 135 . . . . . matches choice B
A student's tuition was $1200. A loan was obtained for 5/6 of the tuition. How much was the loan?
Answer:
the loan was 1000
Step-by-step explanation:
Take the tuition and multiply by 5/6
1200 *5/6
1200/6 *5
200 *5
1000
Answer:
$1000
Step-by-step explanation:
In order to find 5/6 of the tuition, we just need to multiply the 2 values together.
5/6*1200
Note that 1200 = 1200/1
5/6*1200/1
When multiplying fractions, we can multiply the numerators together, and the denominators together.
5*1200/6*1
6000/6
Divide.
1000
Therefore, the loan was $1000.
Any help would be appreciated
Answer:
increase 40
% increase is 40 %
Step-by-step explanation:
Take the new amount and subtract the original amount
140-100 = 40
Divide by the original amount
40/100
.40
Multiply by 100 %
40%
The percent increase is 40%
ASAP! GIVING BRAINLIEST! Please read the question THEN answer CORRECTLY! NO guessing. I say no guessing because people usually guess on my questions.
Answer:
A
Step-by-step explanation:
It is not B because 7x^2 means multiplying the equation by seven. It isn't C because that would move the graph DOWN seven units. And it's not D because when it is in parenthesis like that, it means that it is a horizontal shift, not vertical.
Answer:
A. G(x) = [tex]x^2+7[/tex]
Step-by-step explanation:
→For the function to shift upwards 7 units, 7 must be added to the function, like so:
G(x) = [tex]x^2+7[/tex]
→F(x) + c (in this case is 7), cases a vertical shift and the function is moved "c," units. The graph would shift downwards if 7 was being subtracted.
This means the correct answer is A.
The value z is directly proportional to c. When z = 20, c = 10. Find an equation relating z and c. *
Answer:
a) The equation of Z and C is Z =K C
b) K = 2
Step-by-step explanation:
Explanation :-
Given data Z is directly proportional to C
⇒ Z ∝ C
⇒ Z = K C
The equation of relating Z and C
Z = K C
Given Z = 20 and C =10
20 = K ( 10)
⇒ K = 2
at a coffee shop, the first 100 customers’ orders were as follows
Answer:
81%
Step-by-step explanation:
22+5=27
22/27
The base diameter and the height of a cone are both equal to
x units.
Which expression represents the volume of the cone, in
cubic units?
pix2
2pix3
1/3pix2
1/12pix3
Answer:
[tex]\frac{\pi x^3}{3}[/tex]
Step-by-step explanation:
[tex]V=\pi r^2h\frac{1}{3}[/tex]
[tex]V=\pi x^2x\frac{1}{3}[/tex]
[tex]V=\pi x^3\frac{1}{3}[/tex]
[tex]V=\frac{\pi x^3}{3}[/tex]
[tex]V=1.047198x^3[/tex]
Answer:
Step-by-step explanation:
1/12 pi x ^3
A gun mass of 5 kg fired a bullet of mass 10 g with the velocity of 360 km/h. What
is gun’s velocity of pushing behind?
answer fast please
Answer:
The recoil velocity of the gun is [tex]0.72\,\,\frac{km}{h}[/tex] and is pointing in opposite direction to the velocity of the bullet.
Step-by-step explanation:
Use conservation of linear momentum, which states that the momentum of the bullet (product of the bullet's mass times its speed) should equal in absolute value the momentum of the recoiling gun (its mass times its recoil velocity).
We also write the mass of the bullet in the same units as the mass of the gun (for example kilograms). Mass of the bullet = 0.010 kg
In mathematical terms, we have:
[tex]5\, kg * v= 0.01 \,kg\,* 360\,\frac{km}{h} \\v=\frac{0.01\,*360}{5} \,\,\frac{km}{h}\\v=0.72\,\,\frac{km}{h}[/tex]
Of the mathematics degrees awarded in recent years, 76% were bachelor’s degrees, 21% were master’s degrees and the remaining 3% were doctorates. Moreover, women earned 52% of bachelors, 40% of masters and 22% of doctorates. What is the probability that a randomly chosen mathematics degree was a master's degree given that it was awarded to a woman? Give your answer to 4 decimal places.
Answer:
0.1729 = 17.29% probability that a randomly chosen mathematics degree was a master's degree given that it was awarded to a woman
Step-by-step explanation:
Bayes Theorem:
Two events, A and B.
[tex]P(B|A) = \frac{P(B)*P(A|B)}{P(A)}[/tex]
In which P(B|A) is the probability of B happening when A has happened and P(A|B) is the probability of A happening when B has happened.
In this question:
Event A: Given to a woman.
Event B: Masters degree.
21% were master’s degrees
This means that [tex]P(B) = 0.21[/tex]
Women earned 40% of masters
This means that [tex]P(A|B) = 0.4[/tex]
Probability of the degree being given to a women:
52% of 76%, 40% of 21% and 22% of 3%. So
[tex]P(A) = 0.52*0.76 + 0.4*0.21 + 0.22*0.03 = 0.4858[/tex]
What is the probability that a randomly chosen mathematics degree was a master's degree given that it was awarded to a woman?
[tex]P(B|A) = \frac{0.21*0.4}{0.4858} = 0.1729[/tex]
0.1729 = 17.29% probability that a randomly chosen mathematics degree was a master's degree given that it was awarded to a woman
Use the zero product property to find the solutions to the equation x2 – 9 = 16.
x= -3 or x = 3
x= -6 or x = -3
Ox= -5 or x = 5
O x= 7 or x = 1
Answer:
x = ±5
Step-by-step explanation:
x^2 – 9 = 16
Add 9 to each side
x^2 – 9+9 = 16+9
x^2 = 25
Take the square root of each side
sqrt(x^2) = ±sqrt(25)
x = ±5
Answer:
[tex]x = 5 \: \: \: or \: \: x = - 5[/tex]
Step-by-step explanation:
[tex] {x}^{2} - 9 = 16 \\ {x}^{2} = 16 + 9 \\ {x}^{2} = 25 \\ x = \sqrt{25} \\ x = 5 \\ x = - 5[/tex]
hope this helps
brainliest appreciated
good luck! have a nice day!
What one is it I have have been struggling with this
Answer:
C is the correct answer.
Step-by-step explanation:
The reason it is C is because pi/the symbol on top is irrational.
Hope you have a good rest of your day :)
Which expression is equivalent to 5^10 times 5^5. 5^2 5^5 5^15 5^50
Answer:
5^15
Step-by-step explanation:
(5^10)(5^5)= 5^10+5= 5^15
Describe the rule for the sequence 2, 1, 2/3, 1/2, 2/5, 1/3, 1/7,...
Multiply 2 by 1/2 to get 1.
Multiply 1 by 2/3 to get 2/3.
Multiply 2/3 by 3/4 to get 6/12 = 1/2.
Multiply 1/2 by 4/5 to get 4/10 = 2/5.
Multiply 2/5 by 5/6 to get 10/30 = 1/3.
Multiply 1/3 by 6/7 to get 6/21 = 2/7. (I suspect there's a typo in the question.)
And so on, so that the nth term in the sequence is multiplied by n/(n + 1) to get the (n + 1)th term.
Recursively, the sequence is given by
[tex]\begin{cases}a_1=2\\a_n=\dfrac{n-1}na_{n-1}&\text{for }n>1\end{cases}[/tex]
We can solve this exactly by iterating:
[tex]a_n=\dfrac{n-1}na_{n-1}=\dfrac{n-1}n\dfrac{n-2}na_{n-1}=\dfrac{n-1}n\dfrac{n-2}{n-1}\dfrac{n-3}{n-2}a_{n-3}=\cdots[/tex]
and so on down to
[tex]a_n=\dfrac{(n-1)\cdot(n-2)\cdot(n-3)\cdot\cdots\cdot3\cdot2\cdot1}{n\cdot(n-1)\cdot(n-2)\cdot\cdots\cdot4\cdot3\cdot2}a_1[/tex]
or
[tex]a_n=\dfrac{(n-1)!}{n!}a_1[/tex]
and with lots of cancellation, we end up with
[tex]a_n=\dfrac{a_1}n=\boxed{\dfrac2n}[/tex]
Answer:
Divide 2 by n.
Step-by-step explanation:
Aisha needs to be at least 48 inches tall to ride the colossal coaster at the amusement park. If she grows 5 inches during the next year, Aisha will still not be tall enough to ride. In the context of this situation, what does the inequality x less-than 43 represent?
Answer:
Aisha is shorter than 43 inches.
Step-by-step explanation:
[tex]x+5=48[/tex]
[tex]x=48-5[/tex]
[tex]x=43[/tex]
[tex]x >43[/tex]
Answer:
The answer is B!
Step-by-step explanation:
Test taking! <3
