Question

What does it mean when a chance event has a probability of 4/4

Answer 1

When the probability of something happening is 4/4, it means that the probability of that thing happening is 1

When the probability of an event happening is 1, it means that that the event is going to happen and there is no chance of the event not happening.

Answer 2

When an event has a probability of 4/4, then it means that in 4 times the event might occur for 4 times.

Which that there is a 100% probability that the event may occur.