The probability of rolling a green outcome on one roll is 5/6, and the probability of rolling an orange outcome is 1/6. When rolling the number cube four times, there are different possible outcomes that can result in two greens and two oranges: GGOO, GOOG, OGOG, OOGG. The probability of each individual sequence occurring is (5/6)^2 * (1/6)^2 = 25/1296. Since there are four possible sequences that can result in two greens and two oranges, we multiply this by 4 to get a final answer of:
4 * (25/1296) = **25/324**
Therefore the probability of getting exactly 2 green outcomes and exactly 2 orange outcomes when you roll the number cube four times is equal to **25/324**.