You roll a number cube twice. Find P(even, then not 2). Write the probability as a fraction in simplest form.
The possible outcomes when rolling a number cube are 1, 2, 3, 4, 5, and 6.
The probability of rolling an even number on the first roll is 3/6 or 1/2, since there are three even numbers (2, 4, 6) out of six total.
If the first roll is even and not 2, there are two possible outcomes for the second roll: 1, 3, 4, 5, or 6. There are five possible outcomes for the second roll out of six total, since rolling a 2 would make the entire sequence not satisfy the condition.
Therefore, the probability of rolling an even number on the first roll and a number that is not 2 on the second roll is (1/2) * (5/6) = 5/12.
So, P(even, then not 2) = 5/12.