Solution Found!
Education: Illiteracy USA Today reported that about 20% of
Chapter , Problem 11(choose chapter or problem)
Education: Illiteracy USA Today reported that about 20% of all people in the United States are illiterate. Suppose you take seven people at random off a city street.
(a) Make a histogram showing the probability distribution of the number of illiterate people out of the seven people in the sample.
(b) Find the mean and standard deviation of this probability distribution. Find the expected number of people in this sample who are illiterate.
(c) Quota Problem How many people would you need to interview to be 98% sure that at least seven of these people can read and write (are not illiterate)?
Questions & Answers
QUESTION:
Education: Illiteracy USA Today reported that about 20% of all people in the United States are illiterate. Suppose you take seven people at random off a city street.
(a) Make a histogram showing the probability distribution of the number of illiterate people out of the seven people in the sample.
(b) Find the mean and standard deviation of this probability distribution. Find the expected number of people in this sample who are illiterate.
(c) Quota Problem How many people would you need to interview to be 98% sure that at least seven of these people can read and write (are not illiterate)?
ANSWER:Step 1 of 3
(a) It has been advised to take seven people at random off a city street, and 20% of all people in the United States are illiterate, ie;
n = 7
\(p=20 \%=0.20 \%\)
Determine the probabilities using Table 3 Binomial Probability Distribution in appendix corresponding to the n and p value
\(\begin{array}{l}
P(X=0)=0.210\\
P(X=1)=0.367\\
P(X=2)=0.275\\
P(X=3)=0.115\\
P(X=4)=0.029\\
P(X=5)=0.004\\
P(X=6)=0.000\\
P(X=7)=0.000
\end{array}\)
Using the values of X and P(X) we can make a histogram showing the probability distribution of the number of illiterate people, as shown below.
