A set of events is considered dependent if the outcome of one event affects the outcome of another.
Let's analyze the options provided:
A) The event of getting 2 heads when flipping 2 fair coins.
- These events are independent because the outcome of one coin flip does not affect the outcome of the other.
B) Rolling a number cube and flipping a coin.
- These events are independent because the outcome of rolling the number cube does not impact the outcome of the coin flip.
C) Choosing a marble from a box, replacing it, then choosing another marble.
- These events are independent because the replacement means the first choice does not affect the second choice.
D) Choosing a ball from a bag and then choosing another ball without replacing the first.
- These events are dependent because the outcome of the first choice (the first ball selected) affects what is available for the second choice (the second ball selected).
Therefore, the set of events that is dependent is:
D) Choosing a ball from a bag and then choosing another ball without replacing the first.