Reasoning Puzzle Floor arrangment with family relation(Important in Sbi PO 2017).

Question

There are seven people A, B, C, D, E, F, G living in a building which has seven floors from $(1-7).$ Out of the seven people living six of them belong to a family and in the family, there are two couples. Each couple lives together and has a separate floor and rest of them have separate floors so two floors are empty. The following information is known about them. G is the son-in-law of D. Neither top floor nor first floor is empty. D lives on a floor immediately below that of E. There are two floors between the floors on which the two couples live. C is E’s nephew and lives two floors above the floor on which B lives. A’s sister lives on the $3\text{rd}$ floor.
 

Please answer it with steps or explanations. Thanks in advance

 

Answer 1

Given G is son-in-law of D.. so with this statement we can infer that G is married and D is married and are part of two different couples.

Given C is E's nephew. So now we have following two options for the family tree.

    D <--> B                               D <--> A

 /   /                                         /   /

E   A <--> G                          E   B <--> G

     /                                             /

    C                                            C

Option 1                               Option 2

Note: <--> notation is denoting a couple relation, / is denoting a parent- child relation

With option 1 of the family tree, we cannot derive a floor arrangement that satisfies the given conditions.

But option 2 of family tree we can derive a floor arrangement that satisfies the given conditions as below

7	C
6
5	BG
4
3	E
2	DA
1	F

 

Comments

Thanks Neha...

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Then who is A's sister

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That means E is A’s sister which is a contradiction.