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Determine whether the underlined value represents a parameter or a statistic and why.  86% of all SMC students are from California. 

An SMC student wants to determine the mean amount of financial aid received by students at the college.  How many students should be polled to determine the mean to within $85 at 95% confidence.  Assume that the standard deviation in financial aid is known to be $1400.  

Find the area under the standard normal curve to the right of z = -1.67.

A random sample of SMC math students are asked how much time (in minutes) they spend on math homework per day.  The responses are listed below.  Calculate the 95% confidence interval for the mean time an SMC math students spend on homework per day.  Assume that the conditions are met to calculate the interval.  Round the end points of the interval to one decimal place.  The units of the interval are minutes.  63    67    62    63    41    58    48    42    34    48    

Determine whether or not the following represents a binomial experiment.  If not, why not.  An insurance company chooses a random sample of 20 car accident claims classifying them as single vehicle or multiple vehicle.  They know that 18% of all claims involve a single vehicle.  Let x be the number of single vehicle claims in the sample. 

About 7.2% of all SMC students say that they plan to transfer to a private school.  A random sample of 16 SMC students is chosen.  Find each of the following probabilities. Round each response to four decimal places.  What is the probability that exactly 3 of the 16 chosen students plan to transfer to a private college? [one] What is the probability that more than 3 of the 16 chosen students plan to transfer to a private college. [two]

A poll of 105 visitors entering the Grand Canyon National Park were asked whether they planned on camping while in the park, their state of residence and how many nights they planned to stay.  Answer each of the following.   a) What is the population in this study?  [pop] b) What is the sample in this study? [sam] c) List the variable(s) of interest in this study. [variables]

A school administrator is interested in what percentage of students participate in a summer internship program.  How many students should be polled if the school wants the result to within 3.6% at 90% confidence?  Assume that in a previous summer, 56% of students participated in a summer internship program. 

Suppose you want to test the claim that μ < 35.7. Given a sample size of n = 31 and a level of significance ofα = 0.01, when should you reject the null hypothesis ?

Use the t-table to determine the critical value for a left tailed hypothesis test with a level of significance of 0.025.  The sample size is n = 72.