## Lesson goal: Rolling a dice, twice

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Let's roll one dice two times, and ask some questions about our rolls. In this case, let's see what the probability as a whole is, of getting 4, 5, or 6 on the first roll, and a 1, 2, 3, or 4 on the second roll.

As in last lessons, we'll set N equal to the number of rolls we'd like to make. Next, we'll set up a "roll for-loop" for each roll. The first one study what the probability is to roll a 4, 5, or 6 on dice #1. The second will look for the probability of rolling a 1, 2, 3. A dice roll will be simulated with math.random(1,6).

Note here that we have two separate results, d1 and d2. d1 will be the chance of rolling a 4, 5, or 6. d2 will be the chance of rolling a 1, 2, 3, or 4.

Note a key word in the question, the "and": "getting a 4, 5, or 6 on the first roll and a 1, 2, 3, or 4 on the second roll. "And" in probability means to multiply any separate and independent probabilities, so in the end, we multiply d1 and d2 to find the final answer.