Question
Who among the following lives at the topmost
floor? Study the given information and answer the questions:      Eight people namely C, Q, P, S, W, Z, Y and O live on different floors of eight storey building but not necessarily in the same order. Each of them likes different laptops viz. Dell, Hp, Lenovo, Apple, Asus, Acer, Sony and Microsoft but not necessarily in the same order. Y lives in an even numbered floor but above 4th floor. P doesn’t live on the lowermost floor and at the floor just below or above Y. Four people live between the one who likes Asus and the one who likes Acer. Only one person lives between Q and the one who likes Lenovo. The one who likes Apple lives immediate below the floor on which the one who likes Acer lives. Z doesn’t like Dell and Sony. C likes Lenovo and lives at one of the floor above O. Three people live between Y and the one who likes Dell. P likes Asus and lives on an odd numbered floor. Two people live between Z and the one who likes Apple. S likes Microsoft. The person who likes Sony or Hp doesn’t live at the lowermost floor. W does not like Apple.Solution
By using the given conditions, Y lives in an even numbered floor but above 4th floor. From this there can be two possible cases. Case-1: Y lives on 6th floor and Case-2: Y lives on 8th floor. P likes Asus and lives on an odd numbered floor. P doesn’t live at the lowermost floor and at the floor just below or above Y. In case-1, P lives on 3rd floor and in case-2, P lives either on 5th floor or on 3rd floor. 
Four people lives between the one who likes Asus and the one who likes Acer. From this it is clear that P lives on 3rd floor. The one who likes Apple lives immediate below the floor on which the one who likes Acer lives. Two people live between Z and the one who likes Apple. 
Z doesn’t like Dell and Sony. From this case-2 will be eliminated. Further C likes Lenovo and lives at one of the floor above O. So, C can live on 5th floor only. S likes Microsoft. So, S lives on ground floor and O lives on 2nd floor. The person who likes Sony and HP doesn’t live at the lowermost floor. So, Y likes Sony. W does not like Apple. So, Z likes HP and Q lives on 7th floor. So, the final arrangement is--- 
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