Question

If events A and B are independent, and the probability that event A occurs is 83%, what must be true?

Answer 1

The probability of event B occurring is 17%.
Imagine that you enter 83 raffle tickets and a friend of yours enters 17 tickets. If you two are the only ones who enter, the chance you have (83%) + the chance your friend has (17%) will equal the 100% chance that either one of you or your friend's raffle ticket will be drawn.

I hope this helps!