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
aev [14]
3 years ago
10

Specifications for an aircraft bolt require that the ultimate tensile strength be at least 18 kN. It is known that 10% of the bo

lts have strengths less than 18.3 kN and that 5% of the bolts have strengths greater than 19.76 kN. It is also known that the strengths of these bolts are normally distributed.
a. Find the mean and standard deviation of the strengths

b. What proportion of the bolts meet the strength specification?
Mathematics
1 answer:
Darina [25.2K]3 years ago
3 0

Answer:

Mean strength is 18.94 and your standard deviation is 0.5.

So the proportion of bolts that meet the specifications is 97%.

Step-by-step explanation:

First of all determine the z- scores of these points.There are 10% of bolts with a strength less than 18.3 kN and this normally distributed you can use chart or calculator to calculate z-score. As i have 5% then z-score is -1.28.Then check the other 19.76kN then find that it has a z-score of 1.64.

To check the difference subtract 19.76 and 18.3 then you get 1.46.

Subtract z-scores 1.64 - (-1.28) = 2.92

Then standard deviation is 1.46/2.92 = 0.50

mean of the bolts is obtained by adding 1.28 *0.5 = 0.64 to 18.3 then

subtract 1.64 *0.5 = 0.82 to 19.76

Then mean is 18.94

Mean strength is 18.94 and your standard deviation is 0.5.

For strength specification. First, we find the z-score for this value:

(18-18.94)/0.5=-1.88

the probability of a bolt being made stronger than this z-score.It is approximately 0.97.

So the proportion of bolts that meet the specifications is 97%. .

You might be interested in
PLEASE HELP!!!!
sertanlavr [38]

Answer:

80 students

Step-by-step explanation:

52 + 28 = 80

6 0
3 years ago
Read 2 more answers
Write and solve an equation to find three consecutive integers such that three times the sum of the first two integers is the sa
kherson [118]
Let the integers be x, x+1, and x+2
3(x+x+1)=13+4(x+2)
3(2x+1)=13+4x+8
6x+3=4x+21
2x=18
x=9

the integers are 9,10,11
6 0
3 years ago
Two fair dice are rolled at the same time. What is the probability that one die will show 3 and the other will show 4? A. 1/36
Olin [163]

Answer:

1/36

Step-by-step explanation:

There are 6 numbers on a die. You have a 1/6 chance of rolling a 3 and a 1/6 chance of rolling a 4. 1/6 times 1/6 = 1/36.

5 0
3 years ago
Solve for x. + 5 = 30
sp2606 [1]

Answer:25

Step-by-step explanation:

6 0
3 years ago
21. Randy owns a computer store. In 1990, he sold 150 monitors. In 2000, he sold 900
lutik1710 [3]

Answer:

y=75x+150

Step-by-step explanation:

Let y represent the number of monitors sold.

Given:

x is the number of years since 1990.

So, for the year 1990, x=0.

For the year 2000, 10 years passed. So, x=10.

Now, monitors sold in 1990 are 150. So, at x=0,y=150

Monitors sold in 2000 are 900. So, at x=10,y=900

Thus, the two points are (0,150) and (10,900).

The slope of a line with points (x_{1},y_{1}) and (x_{2},y_{2})  is given as:

Slope, m=\frac{y_{2}-y_{1}}{x_{2}-x_{1}}

For the points (0,150) and (10,900), the slope is given as:

Slope, m=\frac{y_{2}-y_{1}}{x_{2}-x_{1}}\\ m=\frac{900-150}{10-0}\\ m=75

Now, the y-intercept is the point where x=0. So, the point (0,150) has x value as 0.

So, the y-intercept is 150.

Equation of a line in slope-intercept form is given as:

y=mx+b

Where, m is the slope and b is the y intercept.

Here, m=75 and b=150.

Therefore, the equation that represents the above data is given as:

y=75x+150

7 0
3 years ago
Other questions:
  • Which is an advantage of using a credit card? You can make purchases even when you don't have cash. You don't indulge in impulse
    13·2 answers
  • Please help me with question no.1 and 2. chapter ; circles​
    11·1 answer
  • Evaluate 3(x+4)(x+1)<br> (x+2)(x-2) for x=4​
    10·2 answers
  • Wendy's older brother is buying a car.He can make 24 payments of $95 or 30 payments of $80 each. Which costs less?How much less.
    11·2 answers
  • Please help!!!! I am about to fail !!
    8·1 answer
  • What is the measurement TRV
    12·1 answer
  • Please write down the regression model corresponding to these three effects that you considered in part a. What combination of f
    5·1 answer
  • What is the slope of the line? Thank youu
    14·1 answer
  • A bottle-filling process has a low specification limit of 1.8 liter and upper specification limit of 2.2 liter. The standard dev
    10·1 answer
  • Y!!!!!
    10·1 answer
Add answer
Login
Not registered? Fast signup
Signup
Login Signup
Ask question!