Engineering Board Exam Reviewer · Hypergeometric, Poisson, and Geometric Distributions · hard

Customers arrive at an average rate of 4 per hour (Poisson). What is the probability of at most 2 arrivals in one hour?

  1. 0.2381
  2. 0.1465
  3. 0.7619
  4. 0.0733

Answer

A. 0.2381

Solution

P(X≤2)=e-4≤ft(1+4+42/2 )=13e-4=0.2381.

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