<prompt> If a 95 confidence Interval for prevalence of cancer smokers aged 65 years is 56 to 76, the chance that the prevalance could be less than 56 is ?Nil442.505  <response>: Ans. is c i.e., 2.5 In this questions: 56 to 76 confidence interval covers 95 2SD of values. That means 5 of values will fall outside the range of 56-76 --4 2.5 values will be below 56 and 2.5 values will be above 76. 