## Binomial = "two names", e.g., "heads" or "tails"

## Probability of two heads in three coin flips?

## Pr(thh) + Pr(hth) + Pr(hht)

## q * p * p + p * q * p + p * p * q = 3 * p2 * q1

## Multiply p for each head, q for each tail, then multiply by the number of combinations