On 31 Oct 2023, in Country A, There are 400 haunted mansions. In Country B, there are 100 fewer haunted mansions than in Country A but 250 more haunted mansions than in Country C. There are a total of 9000 mansions. What is the total of haunted mansions in countries D, E, F, G, H, I, J, K, L, M, N, O, P, Q, R, S T, U, V, W, X, Y, and Z?