Question in Blood Relation are inevitably asked in examination. The questions are related to our ‘relationships’ in the family. The examiner wants to test your ability to see through the cobweb. It is a test of intelligence and logic. The student is expected to find out ‘relationship’ between two person based on the given ‘input’.
Before we proceed further, let us understand clearly that all relationships are extension of three basic relationships
To solve the questions based on Blood relationships, we can represent them diagrammatically as follows
We follow this as a standardized system so that there is no room for confusion. Based on above information, we can describe any relationship diagrammatically.
Generally two types of questions are asked in the examinations:
Type 1: Jumbled Relationships: These are based on direct relationships and the student is expected to see through and find out the exact relationship between the two persons.
Example 1: ‘My father’s only son’;
Solution: It means either the person himself or if the lady is talking to somebody, then she is talking about her brother.
Example 2: When the examiner says, “My son’s mother”,
Solution: It means the person is talking about his wife.
Example 3: A person state that I have no brother or sister and the person in this photograph is son of my father.
Example 4: Pointing to a photograph, a person says that this is photograph of only daughter in law of his son’s mother. Whom is he talking about?
Solution: If we follow the statement and draw the diagram as follow:-
(Person’s son’s mother is Person’s wife)
Mother’s only ‘Daughter in law’ means that she has only one son and ‘Daughter in law’ is wife of his own son. The person is talking about. So she is ‘Daughter in law’ of the person as well.
Example 5: Pointing to a photograph, a man says, that this is photograph of paternal grandfather of husband of his daughter in law. Whom is he talking about?
Solution: Read the question carefully and draw the diagram following the leads given above:
Example 6: A lady states that this is photograph of only daughter of ‘father- in – law’ of her husband. Whom she is talking about?
Solution: If we draw the diagram using above information, it follows as under:
Since father in law has only one daughter, the lady is wife of the husband she is talking about. It means that it is her own photograph.
Bases on information given to us, it is possible to solve question based on Blood Relationships easily in two ways:-
1) Pictorial ways 2) Analytical Method
The student should start with Pictorial method and after they have clearly understood the pattern, should follow Analytical method to solve the question quickly or easily.
Type 2: Coded Relationships: The relationships are coded in the form of symbols which may be represented by mathematical symbols or in any other form.
The relationships are coded in the form of symbols. It may be stated that A + B means A is father of B. So we note that the relationships between two persons is stated in the form of a symbol and whenever there is a given symbol between the two persons, the relationship of the first to the second is determined by the value given to the symbol. Again, we have to be cautious to note, from where to start. Whether the statement gives us the relationship between ‘A with B’ or of B with A.
In the statement given above, where we are given that A + B means that A is father of B, the equation gives us the relationship of A with respect to B and it states that A is father of B and not vice versa. The relationships can also be given to us in the other format where we may be given the relationship of the person on the extreme right with the person on his left. So we can further categories these relationships into two types:’
1.Relation- Back : We can call this format of coded relationship as Relation–Back’ coding where we start from the right side to left and find out the relationship of the person on the extreme right with the person on the extreme left, starting from extreme right.
A + B means A is father of B.
A – B means A is mother of B.
In both these cases, we are given the relationship of A, who is on the left with the person B who is on his right. We start from right and move towards left. As such we call it Relation – Back.
2. Relation Forward:In this format, the relationship of the person on the extreme right with the person on the extreme left is to be found. In such case we are given the relationship of the person on the right with the person on his left. So we start from the extreme left and find out the relationship of the person on his immediate right. Similarly, the relationship of the person on his right is found. Finally, the relationship of the person on the extreme right is found in respect of the person on the extreme left.
A + B means B is father of A
A – B means B is mother of A
In these case, we are given the relation of the person on the right in respect of the person on his left. So we move from Left to Right and we call it ‘Relation – Forward’ type.
Example 1: If it is given that:
(I) ‘AB’ means ‘A is the father of B’
(II) ‘A – B” means ‘A is the mother of B”.
(III) ‘A B’ means ‘A is the brother of B’
(IV) ‘A ‘B’ means ‘A is the sister of B’.
What is the relationship of P with R in the equation: ‘P + Q x R’.
Step 1: (Identification of the case): We note that this is Relation – Back type of case as we are provided with the relation of person on the left with the person on his right.
Step 2: Now, we find that the sign ‘x’ between two denotes that the person on the left is brother of the person on the right. Following the above lead, we note that Q is brother of R.
Step 3: Now we find the relationship between P and Q. The symbol joining them denotes that the person on the left is father of the person on the right side of the symbol. So P is father of Q.
Step 4: Since P is father of Q and Q is brother of R, therefore P is father of R as well.
Ans. P is father of R. (and not the vice versa. We can not exactly denote the relationship of R with P because we are not given the information with regard to gender of R.
Example 2: If it is given that:
‘A + B’ means ‘B is the father of A’, ‘A – B’ means, ‘B is the wife of A’, ‘A × B’ means ‘B is the brother of A’ and A B means ‘B is the daughter of A’. If S T × U, which of the following is true?
Step 1: (Identification of the case): When we look at the matrix provided to us, we find that it is ‘Relationship –Forward’ type of case since we are provided with the relationship of the person on the right with the person on the left.
Step 2: As it is a case of Relationship Forward, we start from the extreme left and move towards right. We note that the sign ‘’ between the two persons denotes that the person on the right is the daughter of the person on the left. Following this lead, we conclude that T is daughter of S.
Step 3: Next we note that the sign ‘x’ denotes that the person on the right is the brother of the person on the left side of the symbol. From it we conclude that in the equation ‘T x U’, U is brother of T.
Step 4: From Step 2, it is observed that T is daughter of S and from Step 3 we find that U is brother of T, so U is son of S.
Ans. is son of S. We can not even say that S is mother of U because we do not know gender of S but U is definitely male as the symbol shows and so he is son of S.