If a 95% confidence interval for prevalence of cancer smokers aged> 65 years is 56% to 76%, the chance that the prevalence could be less than 56% is-
High-Yield Explanation
Ref:Parks 23rd edition pg 849. 1SD : confidence limit = 68% 2SD : confidence limit = 95% 3SD : confidence limit = 99.7% Given, 95% values lie between 56 and 76% So, 5% values lie below 56 and above 76 altogether . So, 2.5% lies below 56.