Question

47% of citizens in a district voted in the last election. 21% of citizens in the district are under 18. Being younger than 18 and voting in the last election are mutually exclusive. For a randomly selected citizen in the district, answer the following: What is the probability the citizen voted in the last election or was under 18?

Answer 1

68% probability the citizen voted in the last election or was under 18.

Explanation:

Two events are said to be mutually exclusive if one event precludes the other. That means that if A and B are mutually exclusive, the probability of A and B happening at the same time is 0%.

So, the probability of a citizen voting in the last election AND being under 18 is 0%.

What is the probability the citizen voted in the last election or was under 18?

Since these events are mutually exclusive, this probability is the sum of each separate probability.

So there is a 47+21 = 68% probability the citizen voted in the last election or was under 18.