For example I have this problem,
Do Americans tend to vote for the taller of the two candidates in a presidential election? In 30 presidential elections since 1856, 18 of the winners were taller than their opponents. Assume that Americans are not biased by a candidate’s height and that the winner is just as likely to be taller or shorter than his opponent. Find the approximate probability of finding 18 or more of the 30 pairs in which the taller candidate wins.
Based on your answer, can you conclude that Americans consider a candidate’s height when casting their ballot.
To solve this problem I have used normal approximation for binomial distribution. With p=0.5 (because we are assuming that they are unbiased), and found 0.1814
However, I am not sure how to answer the second part of the question, I would like to know at what probability will they consider a candidate's height.