Homework2.pdf. Adobe Acrobat Reader DC File Edit View Window Help Home Tools Hom
ID: 199225 • Letter: H
Question
Homework2.pdf. Adobe Acrobat Reader DC File Edit View Window Help Home Tools Homework2.pdf >* Sign In 115% Poisson probability distribution to obtain probabilities (to four decimal places) and expected frequencies (to one decimal place) for these data. (6 points) Export PDF Create PDF Edit PDF Comment Combine Files Organize Pages v 3. Lead concentrations in the egg shells of California condors have a mean of 1.6 ppm and a standard deviation of 0.4 ppm. The contamination levels of egg shells are classified as "low if the lead concentration is below 1.0 ppm, "moderate" if the lead concentration falls between 1.0 ppm and 2.1 ppm, and "high" the lead concentration is above 2.1. Assuming that the lead concentrations of egg shells follows a normal distribution, answer the following questions. What is the percentile of an egg shell with a lead concentration of 2.3 ppm? (1 point) (b) What lead concentration coITesponds to the 79h percentile? (1 point) (c) What proportion of egg shells are predicted to fall into the "low," "moderate," and (a) "high" ranges? (3 points) Protect Fill & Sign Send for Signature Send & Track t More Tools Store and share files in the Document Cloud Learn More O Type here to search S:11 PM 2/21/2018Explanation / Answer
Using Normal standard distribution equation
Z=x-mean/standard deviation
Given values are
Mean-1.6ppm
S.D-0.4ppm
Low lead concentration-<1.0ppm
Moderate lead concentration-1.0-2.1ppm
Heigh lead concentration->2.1ppm
a)The percentile of egg shell with 2.3ppm of lead concntration-
z=2.3-1.6/0.4
z=0.7/0.4
z=1.75
Area under the standard normal curve z=0.9599
The percentile is 95%
b)Lead concentartion in 79% egg shell-
z for area under stand curve to obrain 79% is 0.81 from z tabel available online
0.81=x-1.6/0.4
0.324=x-1.6
x=1.924
i.e 1.92ppm of lead concentartion in 79% of egg shell
c)Using normal standard distribution
Lower propotion of lead in the egg shell s will come around 1.3
Moderate propotion of lead will fall between 1.3 to 2.87
Heigher propotion more than 2.87
Related Questions
Navigate
Integrity-first tutoring: explanations and feedback only — we do not complete graded work. Learn more.