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Multiple choice questions on a test each have 4 possible answers, one of which is correct.  Assume that you guess the answers to 3 such questions. Use the multiplication rule to find the probability that the first two guesses are wrong and the third guess is correct.  That is, find P(WWC) where W denotes a wrong answer and C denotes a correct answer.  Round your answer to 4 decimal places. [WWC] On your scratch paper, make a complete list of the different possible arrangements of 2 wrong a 1 correct answer.  What is the probability of each combination?  Round to 4 decimal places. [comb] What is the probability of getting exactly 1 correct answer when 3 guesses are made?  Round to 4 decimal places. [one]

In a sample of 1,047 randomly selected adults, 38% said they did not intend to vote in the next election. How many adults in the survey said they did not intend to vote? [one]   In one of Mendel’s experiments with green and yellow peas, 123 out of 515 peas were yellow. What percentage of the peas were yellow?  Round to the nearest tenth of a percent. [two]%   Last year an airline reported that a specific flight was delayed 47 times. This year they reported a 13% reduction in delays for the same flight.  How many times was the flight late this year? [three]

Refer to the table which summarizes the results of testing for a certain disease. Positive Test Result Negative Test Result Subject has the disease 85 7 Subject does not have the disease 28 153 If one of the results is randomly selected, what is the probability that it is a false positive (the test indicates the person has the disease when in fact they do not)?  Give your answer as a decimal rounded to 4 places.

A company considers the production process to be out of control when defects exceed 3%. In a random sample of 85 items, the defect rate is 5.9% but an employee claims that this is only a sample fluctuation and production is not really out of control. The company claims that this is evidence the production process is out of control and the defect rate is greater than 3%. Test the company’s claim at the .01 level of significance. The alternative hypothesis is p [alt] .03 (type , or =/) The p-value is [pvalue] (round to 4 decimal places) The test statistic is z=[test] (round to 2 decimal places) What is your conclusion about the company’s claim? [conclusion]  s = support the company’s claim r = reject the company’s claim f = fail to reject the company’s claim n = not enough evidence to support the company’s claim

Extra credit:  Earn 4 points extra credit The yield of a variety of wheat was measured on a series of small plots and was found to be approximately normal. The 2nd and 98th percentile were found to be 29 bushels/acre and 41 bushels/acre respectively. The standard deviation (bushels/acre) is approximately what? Hint:  Draw a sketch and mark the 2nd and 98th percentiles on the curve.  

Does the table below represent a valid probability distribution?

Find the following probability:  A test consists of 10 true/false questions. To pass the test a student must answer at least 6 questions correctly. If a student guesses on each question, what is the probability that the student will pass the test?  Round your answer to 3 decimal places.  

Two types of flares are tested and their burning times (in minutes) are recorded.  The summary statistics are given below: Brand X Brand Y n=35 n=40 sample mean=19.4 min sample mean=15.1 s=1.4 min s=.8 min Use a .05 significance level to test the claim that the two samples are from populations with the same mean.  Assume that the two samples are independent simple random samples selected from normally distributed populations.  Do not assume the population standard deviations are equal.   The alternative hypothesis is U1 [alt] U2 (type , or =/) The test statistic is:  t=[test] (round to 3 decimal places) The p-value is:  [pvalue] The conclusion about the original claim is:  [claim] s = support the claim r = reject the claim f = fail to reject the claim n = not enough evidence to support the claim

Thirty pairs of data yield r = 0.474 and the regression equation . Also,  the mean of is 18.3.  What is the best predicted value of y for ? 

Use the given data to find the equation of the regression line. Round the final values to three decimal places, if necessary. x 2 4 5 6 y 7 11 13 20 The equation is y = [a] + [b]x