So you see here, she rolled her die 500 times, and she wrote down how many times she got a two. She got a two 110 times, a 395 times, a 470 times, a 575 times, and then she had written down what she got, how many times she got a one and a six, but then it got washed away, so we need to figure out how many times she got a one and a six. Given the information on this table right over here, and given the information that the expected value of the sum of 20 rolls is 67.4. So I encourage you to pause this video and think about it on your own before I give a go at it. So first, let's think about what this expected value, the sum of 20 rolls, being 67.4 tells us. That means that the expected value of one roll, the expected value of the sum of 20 rolls is just 20 times the expected value of one roll. So the expected value of a roll, let me do it here, expected value of a roll is going to be equal to 67.4 divided by 20.