## Elementary Statistics: A Step-by-Step Approach with Formula Card 9th Edition

0 or 3 heads $P(0)=P(3)=0.125$ 1 or 2 heads $P(1)=P(2)=0.375$
While you should do the experiment by tossing three coins 128 times, record the outcomes, and compute the empirical probabilities of each, we can use the binomial distribution to predict the results. $P(x)=nCx\cdot p^xq^{n-x}$ where $n=3, x=0,1,2,3, p=q=0.5$ is the probability of getting a head or tail. We have $P(0)=P(3)=0.125$ and $P(1)=P(2)=0.375$