problem-5.27

problem-5.27  Using the de Moivre-Laplace theorem for the normal approximation gives
> n = 100; p = 1/2; b = 42
> pbinom(b,n,p)
[1] 0.0666
> pnorm(b+1/2, n*p, sqrt(n*p*(1-p)))
[1] 0.06681