saramerguelo
08.04.2020 •
Mathematics
The shear strength of each of ten test spot welds is determined, yielding the following data (psi).
389 405 409 367 358 415 376 375 367 362
(a) Assuming that shear strength is normally distributed, estimate the true average shear strength and standard deviation of shear strength using the method of maximum likelihood. (Round your answers to two decimal places.)
average 382.3 psi
standard deviation 20.8 psi
(b) Again assuming a normal distribution, estimate the strength value below which 95% of all welds will have their strengths. [Hint: What is the 95th percentile in terms of μ and σ? Now use the invariance principle.] (Round your answer to two decimal places.)
psi
(c) Suppose we decide to examine another test spot weld. Let X = shear strength of the weld. Use the given data to obtain the mle of P(X ≤ 400). [Hint:
P(X ≤ 400) = Φ((400 − μ)/σ).]
(Round your answer to four decimal places.)
.
Solved
Show answers
More tips
- C Computers and Internet Connecting Your TV to Your Computer: Easy and Fast...
- L Leisure and Entertainment How to Make a Crab Trap in Just a Few Minutes...
- H Health and Medicine How Much Does Abortion Cost? Expert Answers and Insights...
- S Sport How to Build Arm Muscles? Effective Exercises and Tips...
- H Health and Medicine When can it be said that a person has a normal pulse?...
- A Art and Culture When Will Eurovision 2011 Take Place?...
- S Style and Beauty How to Choose the Perfect Hair Straightener?...
- F Family and Home Why Having Pets at Home is Good for Your Health...
- H Health and Medicine How to perform artificial respiration?...
- H Health and Medicine 10 Tips for Avoiding Vitamin Deficiency...
Answers on questions: Mathematics
- M Mathematics Two soccer balls are simultaneously kicked on parallel paths, from 15 feet apart on level ground. After 0.1 second, the balls are again 15 feet apart. 15 ft Must the two...
- C Computers and Technology (TCO 3) If the numbers 3, 5, 7, 11 are inserted, in that order, in a queue, which will be the last element to be removed? Group of answer choices...
- H History How did collectives in the soviet union avoid the competition that drives a free market economy?...
- H History Exam Instructions Question 4 of 20 : Select the best answer for the question. 4. What was one reason that the Ottoman Sultan Murad used Janissaries i A. The sultan did not...
- C Chemistry Mg(s) + 2 H+(aq) → Mg2+(aq) + H2(g) A student performs an experiment to determine the volume of hydrogen gas produced when a given mass of magnesium reacts with excess HCl(aq)...
- M Mathematics Can someone help me with one of these? Factor using the X method please!...
Ответ:
a) Mean = 382.3 psi
Standard deviation = 20.8 psi
b) 392.7 psi
c) P(X<400)=0.8026
Step-by-step explanation:
a) The population mean can be estimated as equal to the mean of the sample, and the population standard deviation can be estimated from the sample standard deviation:
b) We start by searching for the z-value for the 95th percentile. This value is
z=1.645:
Then, the strength value below which 95% of all welds will have their strengths is:
c) We calculate the probability of X being equal or less than 400 as:
Ответ:
5x+12=6x-10
-5x -5x
12= x-10
+10 +10
X=22