The failure rate is estimated to be 0.04 failures per million hours. The product has accumulated 55,000,000 hours of operation time and 2 failures occurred. What is the probability of getting exactly 2 failures, 2 or fewer failures and more than 2 failures? Using the calculator as indicated, the probability of exactly 2 failures is 0.2681, the probability of 2 or fewer failures is 0.6227 and the probability of more than 2 failures is 0.3773 
Enter:  l  =  0.04 
 t  =  55000000 
 r  =  2 
Press Calculate 
Solves for:  P(2)  =  0.2681 
  =  0.6227 
  =  0.3773 
