The probability of an event= Number of ways an event can occur/ Total number of possible outcomesBoth dices land on values less than 4. This means they both can be 1,2 or 3. Therefore, number of ways the even can occur is in this case 33=9. Total possible outcomes include all the combinations between 1,2,3,4,5 and 6 (the values on the first dice) and 1,2,3,4,5 and 6 (the values on the second dice). It means that the total number of possible outcomes is 66=36. The probability is thus 9/36=1/4=25%.