To ensure that Joe's sample of 10,000 adults is representative and avoids bias, he should aim to select an equal number of participants from each of the 50 states.
To find out how many adults he should choose from each state, you can divide the total sample size by the number of states:
\[ \text{Number of adults per state} = \frac{10,000 \text{ adults}}{50 \text{ states}} = 200 \text{ adults per state} \]
Thus, Joe should choose 200 adults from each state.