This is binomial prob. The number of data points, n, is 12; the chances that an egg will be broken are 0.5, and we want to know the prob. that at least 1 egg is broken. Note that this is the opposite of finding the prob. that none are broken.
Find binompdf(12, 0.5, 0) and sub tract the result from 1.00 to find the desired answer:
binompdf(12,0.5,0) = 2.44*10^(-4)
So the prob. that the customer receives at least 1 broken egg is
1.00000 - 2.44*10^(-4), or 0.9998. Big probability! Buy your eggs elsewhere.