If Phone calls are received to a switch board at a rate of four calls per hour. If the operator leaves his workstation for half an hour what is the probability he will miss a phone call?
I'm also confused to figure whether its related to Poisson distribution or Exponential distribution
**Update:**Sorry I'm still confused which distribution to use. My lecturer said exponential distribution can be used in these kind of scenarios. What is the most suitable type of distribution to be used in this kind of scenario and why?