## College Algebra (10th Edition)

$\begin{array}{cc} &\bf{\text{Outcome}} &\bf{\text{Probability}} \\&HH &0.25 \\&HT &0.25 \\&TH &0.25 \\&TT &0.25\end{array}$ Note: HH means the outcome is head-head
Let H = the outcome of a toss is a head T = the outcomes of a toss is a tail In tossing a fair coin twice, the possible outcomes are: HH, HT, TH, TT. Thus, the sample space is: $S=\left\{HH, HT, TH, TT\right\}$ Since the coin is fair, the outcomes of the sample space are equally likely to occur. Thus, each outcome has a probability of $0.25$ or $\frac{1}{4}$. Therefore, the probability model is: $\begin{array}{cc} &\bf{\text{Outcome}} &\bf{\text{Probability}} \\&HH &0.25 \\&HT &0.25 \\&TH &0.25 \\&TT &0.25\end{array}$ Note: HH means the outcome is head-head