# Introduction

• Family relation / Family tree / Bloodline related aptitude questions are pretty common in CSAT, CMAT, IBPS and CAT.

Let’s try a very clichéd and easy question.

# Dataset #1

There are 6 members in a family: A to F. There are two married couples, D is grandmother of A and mother of B, C is the wife of B and mother of F, F is the granddaughter of E.
Just like our Prime Minister, There is no ‘dum’ in this sum. It requires only three simple steps.

# Step 1: Gender and Generation table

• The data talks about three things: Gender (M/F), Generation(1/2/3) and Blood Relations (mom-son etc.)
• If you try to arrange all three of them simultaneously, it’ll only lead to frustration and wastage of time. So first concentrate on two items only: Gender and Generation. The Relations will fall in line by themselves.

Given data: D is grandmother of A and mother …..
So D is the oldest Generation and she is definitely female.
But we don’t know whether A is male / female.
Anyways fill up the Gender – Generation table

 Generation Male Female Not sure(M/F) 1 Oldest D 2 Mid aged 3 Youngest A

Given data: D is grandmother of A and mother of B
Obviously “B” falls in the 2nd generation (mid-aged) but still we don’t know the gender of “B”.

 Generation Male Female Not sure(M/F) 1 Oldest D 2 Mid aged B 3 Youngest A

Given data: C is the wife of B and mother of F
This one statement, tells us three things

• C is a female and mid-aged (2nd generation)
• B is a male.
• F is 3rd generation. But we don’t know the Gender of “F”

Update the table with this new information

 Generation Male Female Not sure(M/F) 1 Oldest D 2 Mid aged B C 3 Youngest A,F

Given data: F is the granddaughter of E
This tells us following

• F is a female.
• F is 3rd generation (although we knew it already.)
• E is 1st generation and since “D” was female, this has to be male (Granddaddy).

Update the table

 Generation Male Female Not sure(M/F) 1 Oldest E D 2 Mid aged B C 3 Youngest F* A

*intentional mistake.

# Step 2: Checklist

• In the arrangement questions: whether it is circular arrangement, linear arrangement or family tree: always runs the checklist after you’re done arranging the items.
• If you had made any mistake in the arrangement, you’ll find it out at step2.
• IF you proceed directly to solving questions, it may happen that you’ll get all answers incorrect. Because in aptitude tests, they design the 4 answers options (a/b/c/d) in such a way that even if you got incorrect arrangement, you’ll find answers matching to your arrangement!

So here is our final table

 Generation Male Female Not sure(M/F) 1 Oldest E D 2 Mid aged B C 3 Youngest F A

And here is our checklist from the given question data

 Checklist Pass/Fail There are two married couples Pass D is grandmother of A and mother of B Pass C is the wife of B and mother of F Pass F is the granddaughter of E. #EPICFAIL
• Red light. STOP. Checklist item #4 is giving “Fail”
• Haha see? I had made a stupid mistake in the table (intentionally).
• F is granddaughter of “E” but I had mistakenly put “F” in the “Male” column.
• In the actual exam, under the stress, many people make such silly-mistakes.
• They calculate the sum correctly in their head but on the paper, their hand writes a different thing altogether.
• Ofcourse in the actual exam, there is time-limit, so you can’t do cross verification/checklist in each and every aptitude question.
• But in the ‘arrangement’ questions- each dataset comes with 4-5 questions. So, even one silly-mistake will cost you four times the negative marks. Therefore it’s always a good idea to run checklist on arrangement questions.
• Our final “correct” table looks like this
 Generation Male Female Not sure(M/F) 1 Oldest E D 2 Mid aged B C 3 Youngest F A

If you want to construct a family tree, it’ll look like following

Greenlight. Proceed further. Time for some Questions.

# Questions based on the Family-Data

## Q1.Who among the following is one of the couples?

• CD
• DE
• EB
• Cannot be determined
• None of these

well look at the table

 Generation Male Female Not sure(M/F) 1 Oldest E D 2 Mid aged B C 3 Youngest F A

There are two couples : ED and BC
Final answer: (b) DE is one of the couple.

## Q2. Which of the following is definitely false?

• a) A is brother of F
• b) A is sister of F
• c) D has two grandsons
• d) Cannot be determined

From the table

 Generation Male Female Not sure(M/F) 1 Oldest E D 2 Mid aged B C 3 Youngest F A

We are not sure about A’s gender. A can be brother OR sister of F.
So option (a) and (b) are eliminated. We cannot definitely say which of them is false.
But checkout the third option (c), it says “D has two grandsons
Now this is definitely false because we know for sure that granddaughter “F” is a female. So Grandma “D” cannot have two grandsons in any case.

## Q3. How many female members are there in the family?

• 2
• 3
• 4
• Cannot be determined
• None of these.

Since we don’t know the gender of “A”, we cannot determine the number of males and females in this family.

Anyways that was quite an easy dataset. Let’s try something a bit complicated.

# Dataset #2: UPSC CSP’2000

There are 6 people in a family: A to F

• Men and women are in equal number
• A and E are sons of F
• D is the mother of two: one boy and one girl
• B is the son of A
• There is one married couple in the family at present.

# Step #1: Gender and Generation table

Given: Men and women are in equal number

Obviosuly, this means the family has 3 men and 3 women. How else do you distribute 6 into equal numbers otherwise!
Given: A and E are sons of F
It tells us three things

• A and E are males
• F is one generation higher than A,E. It means “F” is definitely not in the 3rd (youngest) Generation.
• But no exact idea about gender or generation of “F”.
 Generation Male Female Not sure(M/F) 1 Oldest 2 Mid aged 3 Youngest 0 (Not Sure) A,E (2/3) F(1/2)

^Notice this time I’ve also made an extra row “0(Not sure)” to accommodate A and E. The (2/3) suggests that A and E can be either 2nd or third generation.
Given: D is the mother of two: one boy and one girl
It tells us two things

• D is female
• D is not the youngest (3rd)generation, because she has kids. Thus She falls either in 1st or in 2nd generation.

Update the table

 Generation Male Female Not sure(M/F) 1 Oldest 2 Mid aged 3 Youngest 0 (Not Sure) A,E (2/3) D(1/2) F(1/2)

Given: B is the son of A
Tells us many things

• B is male. Because opening statement of the dataset said “equal number of men and women” and Since A,E and B are sons (males) therefore C,D and F are females. C is a female but we don’t know her generation: 1/2/3.
• We already know that “A+E are sons of “F”. Therefore A cannot be in 1st generation. (warnaa uski Maa “F” kidhar jaayegi?)
• It means A is definitely 2nd generation male. Because A cannot be 3rd generation (warnaa uskaa Betaa “B” kidhar jayegaa?)
• And Since “A” is second generation, his brother F is also second generation.
• Since A+F are in second generation, their mother “F” has to be first generation.

Update the table with this information

 Generation Male Female Not sure(M/F) 1 Oldest F 2 Mid aged A,E 3 Youngest B 0 (Not Sure) D(1/2) C(1/2/3)

Atleast now we know who is male and who is female. But there is one problem: We don’t know exact generations of female C and D.
Given: D is the mother of two: one boy and one girl
Assume that mom “D” is first generation. But we already know the there are only three males in this family.

• A+E= second generation but sons of F
• B is son of daddy A

So we can’t put “D” is first generation (otherwise 2nd generation mein Tisraa Betaa Kidhar Se Laaoge?)
It means “D” is definitely second generation female. And corollary to that, “C” is third generation female and daughter of mommy “D”. This satisfies the condition
D is the mother of two: one boy(B)and one girl(C)
Update the table

 Generation Male Female Not sure(M/F) 1 Oldest Dead F 2 Mid aged A,E D 3 Youngest B C 0 (Not Sure)

Only one problem remains: Who is the husband of “D”: is it A or is it E?
Given: There is one married couple in the family at present.
Given: B is the Son of A.

From previous steps we already Concluded that: D is mother of B+C
From these three sentences we can derive that B is the son of A+D , therefore A+D are husband and wife.
And A’s brother “E” is middle-aged unmarried clown just like Patrakaar Popatlaal because of his arrogant and obnoxious attitude, no woman is interested in marrying with him.
anyways, I’m drawing this family tree from Grandson “B”’s point of view.

# Step-2: Run the checklist

 Checklist Pass/Fail? Men and women are in equal number Pass: 3+3 A and E are sons of F Pass D is the mother of two: one boy and one girl Pass B is the son of A Pass

Green light. Go on, solve the questions.

# Step-3: Solve the Question

Which of the following inference can be derived from the given dataset?

• i) A,B and C are females
• ii) A is the husband of D
• iii) D is the grandmother of F
• iv) E and F are children of D

From the family tree diagram, we can see that option (ii) is correct: A is indeed the husband of D.

# Do eliminate wrong options

• In some arrangement questions “Two cases” / “two tables”/”Two family trees” may be possible.
• So even after passing the checklist, you may still get incorrect answer; because while doing the arrangement you might have missed some minor detail so you concentrated only on one possible case. You cannot rectify this mistake with checklist alone, because checklist will pass for each of “Two possible cases.” (For example recall the circular arrangement/round table sitting case in previous article.)
• Therefore, when you’re checking the 4 answer options, even if you get correct match in second option(ii), don’t stop just yet, you should still check whether the remaining answer option 1, 3 and 4 are incorrect or not.
 Answer statements True / False Why? A,B and C are females False Dataset itself said A+E are sons of F. So A can’t be a female. A is the husband of D True Table says so. D is the grandmother of F False Table says F is saas and D is her bahu. E and F are children of D False A+E are the sons of F, it is given in the question itself! So E and F cannot be children of D!

Final answer:  A is the husband of D.