Totals Instead of Averages: Airplane Takeoff Time The taxi and takeoff time for commercial jets is a random variable x with a mean of 8.5 minutes and a standard deviation of 2.5 minutes. Assume that the distribution of taxi and takeoff times is approximately normal. You may assume that the jets are lined up on a runway so that one taxies and takes off immediately after the other, and that they take off one at a time on a given runway. What is the probability that for 36 jets on a given runway, total taxi and takeoff time will be (a) less than 320 minutes? (b) more than 275 minutes? (c) between 275 and 320 minutes? Hint: See 19.

Week 1 of Notes : ( Consists of Chapter 1 ) Statistics 1 , Lecture 1 notes in more detail Chapter : Statisti is a waysort out inform, a source to make sense out of certain data. Data is justinformation from an obser ation. A Case known also asobservational , is an individual entibeing observed for data. A Variablis haracterisor trahat vari s. *Depending on the data given, you can determine what the case is that is being observed. 2 Types of Variab s: 1. Categorical variaare observations thaall into different ca example being “groups”. 2. Quantitative varia are also observationsnumerical va it is often the measured amount of someth Remembering that quantitative varialways e a numbers. Remembe