For each question,show what calculator command you entered to get your result.Drawing pictures of each distribution is highly recommended. Contact me for help and clues!

1. A poll is taken of 800 Florida registered voters concerning the presidential race between incumbent Ann Anderson and challenger Bob Bobson. The breakdown of the sample is as follows:

Voting for Anderson:472 voters

Voting for Bobson:273 voters

Voting for third-party candidate:42 voters

Undecided:13 voters

TOTAL800 voters

1. Give a point estimate for the proportion of Florida registered voters who plan to vote for President Anderson.

1. Give a 95% confidence interval for the proportion of Florida registered voters who plan to vote for President Anderson.

1. Give a 95% confidence interval for the proportion of Florida registered voters who plan to vote for Bobson.

1. What is the margin of error for this poll, rounded to the nearest percentage point?(Your answers from ii and iii may differ, but they will round to the same percentage.)

1. An analysis of several polls suggests that 60% of all Florida voters plan to vote for Anderson.
2. A poll of 250 randomly selected Florida voters shows that 144 plan to vote for Anderson. What is the probability of this result (i.e. 144 voters or less out of 250) happening by chance, assuming the aggregate poll model proportion of 60% is correct?

1. Does your result from part I indicate that the number of voters who plan to vote for Anderson has decreased? In other words, is this outcome unusual? (Recall that an unusual event has a probability of 0.05 or less of occurring.)

1. A partisan Florida Web site posts the question "Who do you plan to vote for in the upcoming election?" on their home page, and visitors are invited to pick between Anderson and Bobson. Out of 1505 visitors to their page, 832 of them plan to vote for Anderson. Assuming once more that 60% of Florida voters plan on voting for Anderson, is this outcome (i.e. a proportion of 832/1505 voters or less voting for Anderson) unusual?

1. Give a reason why the results of the poll from part III may have been unusual.("Because the probability is less than 0.05" is not a reason, it's a definition.)

Draw a picture of the distribution for each problem with mean and standard deviations labeled and relevant areas shaded. Show exactly what you entered in to the calculator to arrive at your result, including what function you used and what numbers you entered. Round all decimals to 3 places. Read the questions carefully!

The average life of a new type of motor is normally distributed with mean 10 years and standard deviation 2 years.

1. What proportion of these motors will last somewhere between 8 and 11 years?

1. What's the probability that a randomly selected motor will last more than 15 years?

1. The manufacturer of these motors wants to offer a warranty. If the motor stops working before the warranty period is up, the manufacturer will replace it for free. If that manufacturer is willing to replace only 5% of the motors that they produce, how long should they make the warranty? (In other words, find the number of years n such that 95% of all motors have a lifelongerthan n.)

The average height of adult American men is normally distributed with mean 70 inches and standard deviation 4 inches.

1. What's the probability that a randomly selected adult American man will be less than 75 inches tall?

1. NBA player Kobe Bryant is 6'6" tall. What proportion of adult American men are at least as tall as Kobe?

1. Find the 95^thpercentile of adult American male heights.
2. The Toyota Prius has a mean fuel economy rating of 49.34 mpg with a population standard deviation of 0.46 mpg.
3. What is the probability that a randomly selected Prius gets more than 49.5 mpg?
4. A random sample of 15 Priuses is taken and the miles per gallon for each car are recorded. What is the probability that the mean mpg for this sample is more than 49.5 mpg?
5. A mechanic who services Priuses notices that the mean fuel economy of the 23 Priuses he services is 49.1 mpg. Should he be worried? (In other words, is this sampleunusual? What is the probability of randomly getting a sample like this or worse?)
6. A union wants to get an idea of how many hours per month the average employee is absent from work. 325 employees are randomly selected, and the number of hours each employee misses work is recorded. If the sample has a mean of 8.1 hours and a standard deviation of 5.8 hours,
7. Give a 95% confidence interval for the mean number of hours per month an employee is absent.
8. Give a 99% confidence interval for the mean number of hours per month an employee is absent. How does this interval differ from the one above? Why does this happen?

1. Suppose we know that the population standard deviation for the number of missed hours per month is actually 5.4. Give a 95% confidence interval for the mean number of hours per month an employee is absent, given this new piece of information.

1. For each problem, determine the parameter (,, orp) the problem involves, state the null and alternative hypotheses in terms of that parameter, and state the conclusion based on the results of the hypothesis tests that are given.
2. The mean weight of a can of SD Soda is supposed to be 12 oz. A consumer advocate thinks that SD Soda might be cheating their customers and giving them less than this amount.

Parameter:

H0:

H1:

The consumer advocate finds that there is sufficient evidence to reject the null hypothesis.

Conclusion:

1. A poll from last week shows President Ann Anderson attracting 42% of likely voters. A political scientist would like to know if that proportion has changed since last week.

Parameter:

H0:

H1:

After conducting his own poll, the scientist finds insufficient evidence to reject the null hypothesis.

Conclusion:

1. What does it mean to make a Type I error?

1. What does it mean to make a Type II error?

1. A new cold & flu drug is being tested for possible side effects. It is assumed that the drug is safe, and the tests are looking for evidence to show that it's unsafe, specifically that it has "turns your hair purple" as a possible side effect. In other words:

H0:The drug is completely safe.

H1:The drug causes your hair to turn purple.

1. If you work for the pharmaceutical company developing this drug, what would it mean to make a Type I error in this context?

1. If you work for the pharmaceutical company developing this drug, what would it mean to make a Type II error in this context?
3. If you work for the pharmaceutical company developing this drug, would you rather make a Type I error or a Type II error? Why?