As part of its "Customers First" program, a cellular phone company monitors monthly phone usage. The program identifies unusual use and alerts the customer that their phone may have been used by another person. The following data represent the monthly phone use in minutes of a customer enrolled in this program for the past 20 months.

The phone company decides to use the upper fence as the cutoff point for the number of minutes at which the customer should be contacted. What is the cutoff point?

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