Seven persons A, B, C, D, M, N and O live on different floors of a seven storey building. The bottommost floor is numbered 1 and the topmost floor is numbered 7. Who lives on floor 5? Statement I: A lives two floors above
B. Two persons live between B and O, who lives on floor 1. M lives immediately above N. Statement II: A lives above
C. One person lives between C and
M. O lives below
M. B lives above O but not immediately above O. Statement III: M lives two floors above O. At least three persons live above
M. Two persons live between M and
A. C lives immediately above
B. D lives above
C.

From statement I, as A lives two floors above B. Two persons lives between B and O, who lives on floor 1. M lives immediately above N, so From statement II alone, as A lives above C. One person lives between C and M. O lives below M. B lives above O but not immediately above, so no proper arrangement is possible. From statement III alone, as M lives two floors above O. At least three persons lives above M. Two persons lives between M and A. C lives immediately above B. D lives above C, so Data given in both statements I and III together or both statements I and II together or both II and III is sufficient.