//1.22
clc;
n=2;
k=1;
dof=n-k;
chi_square=(3-5)^2/5+(7-5)^2/5;
disp(chi_square,'Chi square value=')
disp('From the dof and chi square value we find P=0.22')
disp('Hence there are 22% chance that the distribution is just the result of random fluctuations and the coin may be unweighted')