[Solved] Median of the set

They tell us that the numbers in the set {5, 28, 10, 50, x, 7} have the sum of 120, so we can figure out that x=20, which also happens to be the mean. But we are looking for the median. Rearranged the set now looks like {5, 7, 10, 20, 28, 50}. Since 10 and 20 are the numbers in the middle, we'll split the difference and get 15.