If it would be Gaussian distribution. But it is uniform, so you can expect any value between 12 and 120 with same probability.
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It's not Uniform. For instance, getting a 12 or a 120 means you have to roll the exact same value for all 24 dice (either all the highest or all the lowest). Since it's 24d10, your probability of doing either is (1/10)^24
Look at it with two regular dice. The probability of getting 2 or 12 is the lowest, with the probability of 1/36 (1/6 * 1/6). However, you can get a 7 by rolling 1-6, 2-5, 3-4, 4-3, 5-2, or 6-1. Your chances of getting a 7 are 6 times higher than getting a 7 than a 2 or 12.
Though I did just make an estimate about the expected value being 60. With rolling 24d10, between any two pairing of die, you'd reasonably expect 11 to be the highest probable value. With 12 pairings, that's 132 damage. 132/2 is 66. With some quick math, I'd say the expected value is closer to 66.
But it is certainly not a uniform distribution.