1.Assume that a sample is used to estimate a population proportion p. Find the margin of error E that corresponds to the given statistics and confidence level. Round the margin of error to four decimal places.

95% confidence; the sample size is 9900, of which 30% are successes

2.A sample of 4 different calculators is randomly selected from a group containing 48 that are defective and 20 that have no defects. What is the probability that all four of the calculators selected are defective? Round to four decimal places.

3.Given the linear correlation coefficient r and the sample size n, determine the critical values of r and use your finding to state whether or not the given r represents a significant linear correlation. Use a significance level of 0.05.

r =-0.466, n = 15

Assume that a procedure yields a binomial distribution with a trial repeated n times. Use the binomial probability formula to find the probability of x successes given the probability p of success on a single trial. Round to three decimal places.

n = 5, x = 2, p = 0.70