I am interested to know which proper statistical test to use to know the population proportion from a sample taken from the population. For example, a sample of 20 people with 7 persons prefer the red color and 13 prefer the blue color. Which of the following methods should be used to conclude about whether there is a real color preference in the population. 1) binomial distribution with a two tails test assuming a success rate of 0.5 and calculating the sum of probability of x=o to 7 then compare this with 0.05. 2) calculate the population proportion from the sample proportion (7/20) using z- test of single population proportion and check whether 0.5 is included within the range of calculated proportion.