3 In a large city a transportation engineer wants to estimate the proportion of residents who use the bus system regularly Out of a random sample of 2000 residents 1220 use the bus regularly Construct and interpret the 99 confidence interval P hat 1220 2000 61 Q hat 1 61 39 Standard Error 010906 with a Z score of 2 5758 for the 99 confidence interval 61 2 5758 010906 6380 61 2 5758 010906 5819 5819 6380 So with a confidence interval of 99 the true proportion of residents who use the bus system regularly is between 58 19 and 63 8 Suppose we wanted the margin of error for the 90 confidence level to be exactly 2 How many residents 2