Customers Arrive at a Single Self-Serve Coffee Machine in a Busy

question 23

Multiple Choice

Customers arrive at a single self-serve coffee machine in a busy mall at the rate of 20 per hour, following Poisson distribution. Each customer takes exactly 90 seconds to get his or her coffee. What is the expected number of customers in queue at this coffee machine?

• A) 1.0
• B) 1.5
• C) 0.5
• D) 2.0
• E) 3.0

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Definitions:

Self-Serving Bias

The common human tendency to attribute positive events to one's own character but attribute negative events to external factors.

Ethnic Group

A community or population made up of people who share a common cultural background, ancestry, or social experience.

Superior

Often used to describe something that is above average in quality or performance, or higher in position or rank.

Deindividuation

A psychological state characterized by reduced self-awareness and decreased personal responsibility in group settings.