Is the coin fair ? given that sample oberved X = [..............]

1st Method CLT:

We calculate E[X] = Proportion of success

H0 = proportion of fair coin = 0.5

Calculate p value proportion test.

2nd Method Binomial pmf:

Pmf = Bin(n_trials, k_success, p=0.5(fair coin null hypothesis))

CDF 

CDF(less than equal to k) < Alpha(significance level) reject null hypothesis