In a certain code language, R + T means ‘R is the sister of T’. R – T means ‘R is the father of T’. R * T means ‘R is the wife of T’. R ÷ T means ‘R is the mother of T’. Based on the above, how is F related to C if ‘A + B – C ÷ D * E – F ÷ G’?
- (a)Wife
- (b)Daughter
- (c)Daughter’s daughter
- (d)Mother
Answer
Why
Correct — C. Rule: read the chain two letters at a time, left to right, and keep only the links between C and F.
C ÷ D → C is the mother of D.
D * E → D is the wife of E, so D is female.
E – F → E is the father of F, so F is a child of E and his wife D.
F ÷ G → F is the mother of G, so F is female.
F is D's daughter and D is C's daughter, so F is C's daughter's daughter.
Why the others are wrong
- (a)Wife — Nothing in the chain marries F to anyone. The only wife link is D * E, and that makes D the wife of E, not F.
- (b)Daughter — F is one generation too low for 'daughter'. C is the mother of D and D is the mother of F, so F is C's grandchild.
- (d)Mother — The chain runs downwards from C to D to F, so F stands two generations below C. F is indeed a mother — of G, not of C.
Concept
A coded relation chain is read strictly two letters at a time, each symbol applying only to the pair it stands between.
'A + B – C' is two separate facts, not one: A is the sister of B, and B is the father of C.
Write every pair out in plain words, then ignore the letters that are not on the path between the two people asked about.
Sex is fixed indirectly — 'wife of' makes a person female, 'father of' makes a person male — and that is what separates daughter's daughter from daughter's son.
A + B is a decoy for this question. F ÷ G looks like one too, but it does the essential job of fixing F as female, which the option list needs before granddaughter can be told from grandson.
Key facts
- In this code + is 'sister of', – is 'father of', * is 'wife of' and ÷ is 'mother of', with the left letter as the subject.
- 'D is the wife of E' fixes D as female.
- 'E is the father of F' fixes E as male.
- C is D's mother and D is F's parent, so C and F stand two generations apart.
Study next
Common traps
- Reading the chain as one long relation instead of a run of overlapping pairs
- Skipping the sex check and answering 'daughter's son'
- Dragging the decoy link A + B into the path between C and F
SSC defines four symbols and then hands you a chain longer than the question needs — seven letters here for a link that uses four. Draw the tree with each generation on its own row and the answer reads straight off it.
Related PYQs
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