Statistics Question

Given : According to a survey in a country , 31% of adults do not own a credit card. Suppose a simple random sample of 800 adults is obtained . 

Define random variable X denotes number of adults do not own a credit card. 

Let, p denotes proportion of adults who do not own a credit card.  

             p = 31% or 0.31

       n denotes sample size .

              n = 800 

The distribution of X is approximately normal because n $\le$0.05N and np(1-p)$\ge$10 

Provided : 

u_$\hat{p}$ = 0.31 
s_{$\hat{\mathrm{p}}$} = 0.016