Trina rolled a number cube three times determine the probability of rolling and even number on each roll

1/2 x 1/2 x 1/2 = 0.125

Assuming the dice is six-sided, we know that there are three even numbers. 3/6 can be simplified to 1/2. Since you want to get an even number three times, and you are using the same dice, you must multiple 1/2 by itself three times.