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What is the best predicted shape of a data set if the mean is 100 and the median is 70?

Consider the following uniform distribution.  What is the probability that the random variable has a value less than 2? 

You take a random sample from some population and form a 96% confidence interval for the population mean. Which quantity is guaranteed to be in the interval you form?  

The state of Iowa is studying the relationship between the rainfall in a season (in inches) and the number of bushels of corn produced per acre of land.  A random sample of growing seasons is selected and the data is recorded in the table below.  Rainfall inches( (x) Bushels of Corn per acre (y) 11.5 46.5 9.8 42.2 14.4 64.8 19.8 78.4 11.3 45.2 8.0 20.9 16.6 72.0 17.0 74.8 1. Find the linear correlation coefficient r for this data set.  Round to three decimal places. [r] 2. A hypothesis test is to be done to determine if there is linear correlation between these two variables.  The null and alternative hypotheses are given below.  Use a 0.05 level of significance.          

In a study of 100 Honda Fit cars it was found that the mean fuel economy was 38 mph.  What are the population and variable in this study? population [pop] variable [sam]

A linear correlation is found between the diameter of a tree in inches (x) and the age of a tree in years (y) with r = 0.951.  The equation of the regression line is y = 6.1 + 7.23x.  Which of the following is the correct contextualized interpretation of r2, the coefficient of determination.  Use the interpretation from our class notes only. 

Suppose you want to find the confidence interval at a confidence level of 80% confidence.  What is the corresponding critical value, 

A study is to be done to determine the proportion of SMC students that plan to transfer to a Cal State University.  Students are divided into groups by intended major and a random sample of 12 students is chosen from each major.  This is an example of what type of sampling?

Determine whether the sampling is independent or dependent and whether the variable is qualitative or quantitative.  A researcher randomly selects 500 people aged 19 – 29 and records whether or not each owns a car.  She then selects 500 people aged 30 – 39 and records whether or not each owns a car.  The proportion of car owners in the two age groups will be compared. 

A study is to be done to determine if type of college (public 4-year, private 4-year, community college) and the acceptance of credit cards for tuition payments are independent.  A random sample of colleges is polled and the data is recorded in the table below.   Accepts Credit Cards Does not Accept Credit Cards Public 4 – year 84 16 Private 4 – year 78 35 Community College 103 7 Use this information to complete test for independence at a 0.05 level of significance.  1. What are the null and alternative hypotheses for the test for independence in this situation.       Ho:  [null]      H1: [alt] 2. Find the test-statistic and the p-value for the hypothesis test.       Test-Stat:   [TS]      p-value: [p] 3. What is the initial conclusion?  [initial]  Why? [why] 4.  In the table of expected values, what is the entry for the cell corresponding to Community College and Accepts Cards?  [ans4] 5. Why did this data set meet the criteria for completing the hypothesis test?       All [obs] frequencies are greater than or equal to [five].