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When one long wait changes the average

An average wait can sound straightforward until one person waits much longer than everyone else. The mean and median offer two ways to summarize that same group. Their different responses to an unusually large value raise a practical question: what do we want an average to tell us?

5–7 min

Questions you could explore

  • Why can a longer wait change the mean while leaving the median unchanged?
  • When would changing one waiting time change the median too?
  • What can either summary leave out about people's experiences?

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