What does a probability of 0.5 indicate about the likelihood of an event occurring?

A probability of 0.5 signifies that there is an equal chance of an event occurring or not occurring. This means that, in a large number of trials, we would expect the outcome to happen half the time and not happen the other half, reflecting a balanced likelihood.

When we think of probability, a value of 0 represents an event that cannot happen at all, and a value of 1 indicates an event that is guaranteed to occur. Thus, a probability of 0.5 lies precisely in the middle, suggesting that the occurrence and non-occurrence of the event are equally likely. This is often illustrated using a fair coin flip, where there's a 50% chance of landing heads and a 50% chance of landing tails, demonstrating the concept of equal likelihood.