We have all had to plan a trip to the airport. Sometimes it goes well and sometimes not so well. One of the problems we have is dealing with the variation in the trip time to the airport. Since I travel to the airport a lot and like analyzing data, I keep track of my travel time to the airport. And living in Boston has always been an adventure when going to the airport.

Our question today (or our problem statement) is simple: “How much time should I allow for my trip to the airport so I don’t miss my plane?”

Here in figure 1 is a run chart (data over a time period) that shows my trips to the airport over time. The numbers on the left show my total trip time in minutes—from leaving the house until completing the security check in the airport. Note that I have made 58 trips to the airport and that my average time to get there is 93 minutes. 

Figure 1: Trip Times to Airport (minutes on left, number of trips at bottom)

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