In: Statistics and Probability
In a certain presidential election, Alaska's 40 election districts
averaged 1,951.8 votes per district for a candidate. The standard
deviation was 572.3. (There are only 40 election districts in
Alaska.) The distribution of the votes per district for one
candidate was bell-shaped. Let X = number of votes for
this candidate for an election district.
1. State the approximate distribution of X. (Enter your numerical values to one decimal place.)
2. Is 1,951.8 a population mean or a sample mean? How do you know? (1) A population mean, because all election districts are included. (2) A population mean, because only a sample of election districts are included. (3) A sample mean, because only a sample of election districts are included. (4) A sample mean, because all election districts are included.
3. Find the probability that a randomly selected district had fewer than 1,600 votes for this candidate. (Round your answer to four decimal places.)
4. Write the probability statement.
5. Find the probability that a randomly selected district had between 1,800 and 2,000 votes for this candidate. (Round your answer to four decimal places.)
6. Find the third quartile for votes for this candidate. (Round your answer up to the next vote.)