### Video Transcript

What is the probability of rolling a number which is divisible by two on a fair die?

A fair die is a cube with six faces. They are numbered one, two, three, four, five, and six. The probability of an event occurring can be written as a fraction, where the numerator is the number of successful outcomes and the denominator is the number of possible outcomes.

In this case, the number of successful outcomes are all of those that are divisible by two. All even numbers are divisible by two. The even numbers on a die are two, four, and six. Therefore, all three of these are divisible by two. As there are three numbers that are divisible by two, our numerator, the number of successful outcomes, is three.

The denominator is equal to six as there is six possible outcomes on a die. This fraction can be simplified by dividing the numerator and denominator by three. Three divided by three is equal to one, and six divided by three is equal to two. This means that the probability of rolling a number which is divisible by two on a fair die is one-half or one out of two.