Answer:
16/52, or 4/13.
Step-by-step explanation:
First, since we know that the question is asking for the probability of a club or a jack, we know that we have to add the two probabilities. The first probability is that of picking a club, which is 13/52. The probability of picking a jack (be sure not to overlap; don't double count the jack of clubs) is 3/52. Adding these two gives us 13/52+3/52=16/52, which simplifies to 4/13.