The probability of rolling any number on a die is 1/6. If you were to roll a die 5 times in row and each time you rolled an even number what is the probability of rolling an even number on the next roll?
These events are independent, meaning that the outcome of one does not affect the outcome of another event. Thus, since there are 3 even numbers and 6 total numbers, you divide 3 by 6 to get a fraction 1/2
