57 264
Assignments Done
Successfully Done
In February 2018
Your physics homework can be a real challenge, and the due date can be really close — feel free to use our assistance and get the desired result.
Be sure that math assignments completed by our experts will be error-free and done according to your instructions specified in the submitted order form.
Our experts will gladly share their knowledge and help you with programming homework. Keep up with the world’s newest programming trends.

Answer on Statistics and Probability Question for alyssa

Question #2823
Dr. Al Kali, an environmental chemist, measures the pH of numerous samples of water collected from a polluted lake. His data are normally distributed with a mean pH of 8.25 and a standard deviation of 0.35. What should Dr. Kali report as the margin of error for the 90% confidence interval for his data?
Expert's answer
Let X ne the pH of numerous samples of water collected from a polluted lake.
By assumption X has normal distribution N(8.25,0.35).
Then Z=((X-8.25)/0.35) has normal distribution N(0,1).

Then margin of error is equal to
δ = 0.35 * z, where z is such that
P(-z< Z < z) = 0.9
If Φ is a c.d.f. for N(0,1), then
z= - Φ-1 ((1-0.9)/2)= -Φ-1 (0.05)= 1.645

δ = 0.35 * 1.645 = 0.576

Need a fast expert's response?

Submit order

and get a quick answer at the best price

for any assignment or question with DETAILED EXPLANATIONS!


No comments. Be first!

Leave a comment

Ask Your question