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
guapka [62]
3 years ago
6

The Rockwell hardness of a metal is determined by impressing a hardened point into the surface of the metal and then measuring t

he depth of penetration of the point. Suppose the Rockwell hardness of a particular alloy is normally distributed with mean 69 and standard deviation 2.7.
a. If a specimen is acceptable only if its hardness is between 67 and 75, what is the probability that a randomly chosen specimen has an acceptable hardness?
b. If the acceptable range of hardness is (69-C, 69+C), for what value of C would 95% of all specimens have acceptable hardness?
c. If the acceptable range is as in part (a) and the hardness of each of ten randomly selected specimens is independently determined, what is the expected number of acceptable specimens among the ten?
d. What is the probability that at most eight of ten independently selected specimens have a hardness of less than 72.84(HINT Y=number among the ten specimens with hardness less than72.84 is a binomial variable; what is p?)
Mathematics
1 answer:
gayaneshka [121]3 years ago
7 0

Answer:

Answer for the question:

The Rockwell hardness of a metal is determined by impressing a hardened point into the surface of the metal and then measuring the depth of penetration of the point. Suppose the Rockwell hardness of a particular alloy is normally distributed with mean 69 and standard deviation 2.7.

a. If a specimen is acceptable only if its hardness is between 67 and 75, what is the probability that a randomly chosen specimen has an acceptable hardness?

b. If the acceptable range of hardness is (69-C, 69+C), for what value of C would 95% of all specimens have acceptable hardness?

c. If the acceptable range is as in part (a) and the hardness of each of ten randomly selected specimens is independently determined, what is the expected number of acceptable specimens among the ten?

d. What is the probability that at most eight of ten independently selected specimens have a hardness of less than 72.84(HINT Y=number among the ten specimens with hardness less than72.84 is a binomial variable; what is p?)

is given in the attachment.

Step-by-step explanation:

Download pdf
You might be interested in
Amanda has a piece of ribbon that is 1/4 yard long. She wants to sharethe ribbon with 2 friends so that they can each wear a rib
Naddik [55]
So is there 2 friend or 3

7 0
3 years ago
Read 2 more answers
Which of the following is a solution of x2 + 2x + 8?
zubka84 [21]
Using the quadratic equation we get:
\frac{ - 2 + - \sqrt{4 - 32} }{2} = \frac{ - 2 + - \sqrt{ - 28} }{2}

Factoring out 2 we get
\frac{ - 2 + - 2\sqrt{ - 7} }{2} = - 1( + - ) \sqrt{ - 7}
Factoring out the imaginary number:
- 1 + \sqrt{7} i \: (and) \: - 1 - \sqrt{7} i
So b.
4 0
3 years ago
What is Szymborska's overall opinion of humanity in "A Contribution to Statistics?" Support your response with at least two deta
aleksandrvk [35]

Answer:

Szymborska's overall opinion of humanity in "A Contribution to Statistics" is overall positive

Step-by-step explanation:

Szymborska is a poet who likes to comment on society with irony and sarcasm.One example of this is when she splits people into categories in her poem “A Contribution to Statistics”. Here Szymborska’s overall opinion of humanity may seem negative due to her bluntness and dry humor. For example, she says in the tenth stanza, “cruel when forced by circumstances -better not to know even ballpark figures.” It’s implied in this line that most people (maybe even all)are cruel or can be. She also says, “taking only things from life -thirty”which comments how lots of people are selfish. However, this seemingly cynical poem takes a sweeter turn near the end with statistics like, “worthy of compassion - ninety-nine” and “mortal- a hundred out of a hundred.” These lines reveal that even though Szymborska believes that humanity is extremely flawed the mass majority of us deserve and are worthy of love. Plus the fact that we’re all mortal may seem dark but the fact remains that both the righteous and the sinners will all end up in the same place. The fact that no one can escape

death gives humans equality in a way. Szymborska’s overall opinion of humanity turned out to be more optimistic after all.

8 0
4 years ago
Read 2 more answers
Which ratio is equivalent to 3/15
Rzqust [24]

Answer:

Step-by-step explanation:

The ratio of 6:30 would be equivalent to it.

4 0
3 years ago
find the sum ofthe angle measure in each regular polygon. Then find the measure of each angle. Show work please I'm so bad at th
Tems11 [23]
For every side you just add 90 to your equation. so #4 would be 360-125-125-55=(55)
6 0
3 years ago
Other questions:
  • You are repairing a fence and have 7.9 metres of wood. You need 10 metres.
    13·1 answer
  • Will somebody give me a hand
    10·1 answer
  • Problems 11-16, find the domain of each function.
    14·1 answer
  • The cube in the image has a volume of 1,000 cubic feet. The other solid has the same base and height as the cube, but the length
    7·1 answer
  • can someone explain how this example answer is the answer, this is about mixed to improper fractions and i dont know how to do t
    12·1 answer
  • Find the value of x y and z​
    9·1 answer
  • A trough has ends shaped like isosceles triangles, with width 2 m and height 5 m, and the trough is 18 m long. Water is being pu
    13·1 answer
  • Wichanges saved
    7·2 answers
  • un almacén de pinturas utiliza 2/3 de la superficie para almacenar pinturas, 1/4 del resto para disolventes y los 600m² restante
    5·1 answer
  • (6m^5 g^5)^2 simplify
    10·1 answer
Add answer
Login
Not registered? Fast signup
Signup
Login Signup
Ask question!