MATH-2314 : Test 3 Review Fall 15
Document Summary
Math 2314: a random sample of 50 people was asked to keep a record of the amount of time spent watching television in a specified week. If the sample mean was 24. 4 hours and the sample standard deviation was 7. 4 hours, give a 95% confidence interval estimate for the average time spent watching television by all members of the population that week. What is the margin of error: dr. stanley wants to estimate the mean age of all u. s. millionaires. He randomly collected a sample of 36 u. s. millionaires and calculated a mean age of 58. 53 years. Determine a 95% confidence interval for the mean age of all u. s. millionaires. Assume that the standard deviation of ages of all u. s. millionaires is 13. 0 years: the weights of ball bearings are normally distributed with standard deviation 0. 5 millimeters. Assume the distribution is normal: an individual"s present route to work results in, on average, 40 minutes of travel time per trip.
