The Florida Department of Transportation FDOT would like to
Last updated: 4/6/2023

The Florida Department of Transportation FDOT would like to estimate the average speed of vehicles on 1 95 The mean speed in miles per hour of a random sample of vehicles was found to be 89 miles per hour The standard deviation of the speeds of all vehicles on 1 95 is known to be 11 miles per hour Find three different confidence intervals one with sample size 51 one with sample size 298 and one with sample size 536 Assume that the mean of each sample is 89 miles per hour Notice how the sample size affects the margin of error and the width of the interval Report confidence interval solutions using interval notation Round solutions to two decimal places if necessary When n 51 the margin of error for a 95 confidence interval is given by When n 51 a 95 confidence interval is given by When n 298 the margin of error for a 95 confidence interval is given by When n 298 a 95 confidence interval is given by When n 536 the margin of error for a 95 confidence interval is given by When n 536 a 95 confidence interval is given by If the sample size is increased leaving all other characteristics constant the margin of error of the confidence interval will Select an answer If the sample size is increased leaving all other characteristics constant the width of the confidence