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
Need help will 11&12!
Zinaida [17]

Answer:

11.)60 degrees the lines on the triangle (the lil dashes) mean that that all the sides are equal making all the angles equal as well so all the angles equal 60 degrees.

12.) no, because in order for all the sides to be 12ft the angles have to be 60 degrees and this one is only 58 degrees so it wont exactly reach 12ft

Step-by-step explanation:

hope this helps :P

5 0
3 years ago
PLEASE HELP ME!!!
Dovator [93]
Stairs because they can’t possibly walk up the stairs cause then they’ll fall
8 0
3 years ago
Read 2 more answers
1. what is 10% of 20? 2.What is 5% of 10?
Airida [17]
Hello,

Shall we begin?

1. what is 10% of 20?      = 20 * 0.1 = 2
2.What is 5% of 10?        = 10 * 0.05 = 0,5
3. What is 25% of 100?   = 100 * 0,25 = 25
4. What is 15% of 50?     = 50 * 0.15 = 7,5
5. What is 30% of 60?     = 60 * 0,3 = 18
6. What is 50% of 80?     = 80 * 0,5 = 40
7. What is 20% of 120?   = 120 * 0,2 = 24
8. What is 35% of 70?     = 70 * 0,35 = 24.5
9. What is 75% of 150?   = 150 * 0,75 = 112.5
10. What is 60% of 90?   = 90 * 0,6 = 54
11. What is 40% of 40?   = 40 * 0,4 = 16
12. What is 55% of 110? = 110 * 0.55 = 60.5
13. What is 80% of 130? = 130 * 0,80 = 104



5 0
3 years ago
Read 2 more answers
Write the contrapositive and the converse of the following conditional
Lunna [17]

The contrapositive statement are:

  • If the lake is frozen, then it isn't cold.
  • If Solomon is happy, then  he isn't healthy.
  • If Tigist  does not take a walk, then it will not rain

<h3>What is the converse statement?</h3>

The  converse statement are:

  • If the late is frozen, then it is cold.
  • If Solomon is happy, then he is healthy.
  • If Tigist Tigist  does not take a walk, then it will rain.

Note that the converse of a statement is created by the act of switching the hypothesis given and also the conclusion.

Therefore, The contrapositive statement are

  • If the lake is frozen, then it isn't cold.
  • If Solomon is happy, then  he isn't healthy.
  • If Tigist  does not take a walk, then it will not rain

Learn more about contrapositive statement  from

brainly.com/question/1713053

#SPJ1

6 0
2 years ago
Read 2 more answers
Fred bought 7 games on clearance for $104.65. Each game was on sale for the same price. How much did each game cost? (Show your
NISA [10]

Answer:

Each game cost $14.95.

Step-by-step explanation:

104.65 = 7x

104.65/7 = x

14.95 = x

3 0
3 years ago
Other questions:
  • Use the distributive property to expand the expression. 2(a2 − 5b) − (c2 − 1)
    7·1 answer
  • A cheetah runs at a speed of 150 kmph. It covers a distance of 750 m in:
    14·1 answer
  • The side of a square is 3 cm smaller than one of the sides of a rectangle and 2 cm greater than its other side. Find the side of
    6·1 answer
  • What is equivalent to 16 + (48 - 12) \ 6 - 5 * 2
    9·1 answer
  • What’s the definition of dependent events?
    11·2 answers
  • The total amount of money (in cents) in x nickels, (x+5) dimes and 2x quarters
    12·1 answer
  • Catherine's mother is
    14·1 answer
  • Evaluate the following expression when x = 6 and y = 2:
    7·2 answers
  • 2×+3=24 whats does the x stands for<br>​
    9·1 answer
  • Mia is finally able to upgrade her cellphone.The one she wants costs $220 but she can get it for 60% off
    10·2 answers
Add answer
Login
Not registered? Fast signup
Signup
Login Signup
Ask question!