1answer.
Ask question
Login Signup
Ask question
All categories
  • English
  • Mathematics
  • Social Studies
  • Business
  • History
  • Health
  • Geography
  • Biology
  • Physics
  • Chemistry
  • Computers and Technology
  • Arts
  • World Languages
  • Spanish
  • French
  • German
  • Advanced Placement (AP)
  • SAT
  • Medicine
  • Law
  • Engineering
andrew-mc [135]
3 years ago
9

The strength of a certain type of rubber is tested by subjecting pieces of the rubber to an abrasion test. For the rubber to be

acceptable, the mean weight loss μ must be less than 3.5 mg. A large number of pieces of rubber that were cured in a certain way were subject to the abrasion test. A 95% upper confidence bound for the mean weight loss was computed from these data to be 3.45 mg. Someone suggests using these data to test H0 : μ ≥ 3.5 versus H1 : μ < 3.5. It is discovered that the mean of the sample used to compute the confidence bound is X⎯⎯⎯ = 3.40. Is it possible to determine whether P < 0.01? Explain. Round the test statistic to two decimal places and the answer to four decimal places.
Mathematics
1 answer:
My name is Ann [436]3 years ago
8 0

Answer:

Step-by-step explanation:

Hello!

You have the hypothesis that the average weight loss for rubber after an abrasion test is less than 3.5 mg. To test this a large sample of pieces of rubber were sampled and subjected to the abrasion test.

With the given information you must test whether the researcher's hypothesis is sustained or not.

The study variable is,

X: Weight loss of rubber cured in a certain way after being subjected to the abrasion test. (mg)

There is no information about the variable distribution, but since it is said that the sample is a "large number" I'll take it as if it is bigger than 30 and apply the Central Limit Theorem to use the approximation of the sample mean to normal. This way I can use the Z-statistic for the test.

Symbolically the statistic hypothesis is:

H₀: μ ≥ 3.5

H₁: μ < 3.5

α: 0.05 (since is not listed, I'll choose one of the most common signification levels)

You have a one-tailed critical region, this means the p-value will also be one-tailed to the left of the distribution (i.e. →-∞)

The formula of the statistic is:

Z= <u> X[bar] - μ </u> ≈ N(0;1)

        δ/√n

To calculate the statistic you have to use the information given.

The sample mean X[bar]= 3.4 mg

Upper bond of 95% CI= 3.45 mg

The basic structure of a CI for the mean is

"estimator" ± "margin of error"

Upper bound is "estimator" + "margin of error"

Using the formula:

Ub= X[bar] + d ⇒ 3.45= 3.4 + d

⇒ d= 3.45 - 3.4 = 0.05

Where d is the margin of error

d= Z_{1-\alpha /2} * (δ/√n)

d= Z_{0.975} * (δ/√n)

d/Z_{0.975}= (δ/√n)

(δ/√n)= 0.05/ 1.96 = 0.0255

(δ/√n) is the denominator in the formula, corresponds to the standard deviation of the distribution.

Now you have all values and can calculate the statistic under the null hypothesis:

Z= <u> 3.4 - 3.5 </u> = -3.92

       0.0255

And the p-value:

P(Z ≤ -3.92) = 0.000044 ⇒ My Z- table goes up to P(Z ≤ -3.00) = 0.001, so using strictly the table I can say that the probability is less than 0.001.

To calculate the exact probability I've used a statistic program.

p-value < 0.001

I hope it helps!

You might be interested in
18. Which expression is equivalent to
Amanda [17]

Answer:

D. 14x

Step-by-step explanation:

add 9x to 4x which is 13x then add x to 13x which is 14x

6 0
3 years ago
Which of these represents the equation of a line that passes through the points (-5, -4) and (3, 8)?
Deffense [45]
The answer is a I just did it :)
3 0
3 years ago
The shape on the left is transformed to the shape on the right. Figure A B C D is rotated to form figure A prime B prime C prime
kotegsom [21]

Answer:

A

Step-by-step explanation:

I did the test and it is the only one that makes sense

7 0
3 years ago
Read 2 more answers
Which option below demonstrates the correct interval notation for a
Vladimir [108]

The correct interval notation for the continuous set of all numbers between 5 and 6, including 5, but not including 6 is [5, 6) option (C) is correct.

<h3>What is interval notation?</h3>

It is defined as the representation of a set of values that satisfy a relation or a function. It can be represented as open brackets and close bracket the close the brackets means the value is at the close bracket also included, and open bracket means the value at the open bracket does not include.

We have:

Continuous set of all numbers between 5 and 6, including 5, but not including 6.

From the above statement we can represent the number in the interval notation:

The numbers are between 5 and 6.

(5, 6)

As it is mentioned that 5 is included and 6 is not included, then:

[5, 6)

Thus, the correct interval notation for the continuous set of all numbers between 5 and 6, including 5, but not including 6 is [5, 6) option (C) is correct.

Learn more about the interval notation here:

brainly.com/question/13048073

#SPJ1

3 0
2 years ago
The radius of a circle is 3<br> kilometers. What is the<br> circumference?
tino4ka555 [31]
The circumference is found by the multiplying the diameter by pi so 3+3=6 so 6*3.14=18.84 ANSWER IS 18.84
7 0
3 years ago
Other questions:
  • Problem 9-10 The elongation of a steel bar under a particular tensile load may be assumed to be normally distributed, with a mea
    10·1 answer
  • Can someone plz help me
    11·1 answer
  • 1/15 greater or less than 10/18
    14·1 answer
  • Can someone tell me how to do <br> variously proportional and proportional situations
    8·1 answer
  • Clinical Trial When XELJANZ (tofacitinib) was administered as part of a clinical trial for this rheumatoid arthritis treatment,
    7·1 answer
  • AB=10,BC=6. What is AC
    15·1 answer
  • I need help with this question
    15·2 answers
  • Can someone plz help meeee!!!!
    6·1 answer
  • The graph below have the same shape what is the equation of the blue
    5·1 answer
  • Scores on a graduate school entrance exam follow a normal distribution with a mean of 560 and a standard deviation of 90. What i
    12·1 answer
Add answer
Login
Not registered? Fast signup
Signup
Login Signup
Ask question!