A survey of several 8 to 11 year olds recorded the following amounts spent on a trip to the mall: $19.36, $29.95, $7.82, $8.36, $21.07, $14.06, $22.22 Construct the 80% confidence interval for the average amount spent by 8 to 11 year olds on a trip to the mall. Assume the population is approximately norm Co Step 1 of 4: Calculate the sample mean for the given sample data. Round your answer to two decimal places.

A teacher would like to estimate the mean number of steps students take during the school day. To do so, she selects a random sample of 50 students and gives each one a pedometer at the beginning of the school day. They wear the pedometers all day and then return them to her at the end of the school day. From this, she computes the 98% confidence interval for the true mean number of steps students take during the school day to be 8,500 to 10,200 steps. Which of these statements is a correct interpretation of the confidence level? A) Approximately 98% of students take between 8,500 and 10,200 steps per day. B) The teacher can be 98% confident that the interval from 8,500 to 10,200 captures the true mean number of steps taken by students during the school day. C) If many random samples of size 50 are selected from all students at this school, approximately 98% of the intervals would capture the true mean number of steps taken during the school day. D) Approximately 98% of the…

The following data represents the monthly cost for telephone service for a random sample of 8 households in Wilmington. 43, 47, 51, 36, 50, 42, 38, 41, 39 Construct a 95% confidence interval for the population average monthly expenditure

2) The following data represent the number of passengers per flight in a random sample of 20 flights from Vienna, Austria, to Cluj-Napoca, Romania, with a new airline: 96 95 70 74 28 63 64 94 37 83 25 48 80 52 48 52 38 47 79 65 a) Find a 99% confidence interval for the mean number of passengers per flight. b) Find a 95% confidence interval for the population standard deviation.