Worked examples: direction before labels
Start with the words, not a shortcut
A parent is a mother or father; a child is their son or daughter. “A is B’s mother” tells us that A is female and A is B’s parent. It does not tell us B’s gender. Letters are only name tags.
We draw parent → child. You may travel against an arrow when solving, but do not reverse the fact it records. “What is A to C?” means: stand at C and name A’s relationship to C.
Mother’s mother = maternal grandmother; father’s mother = paternal grandmother. In Hindi these are नानी and दादी. The first parent reached from the child decides the branch.
In this course, use only explicit links. A marriage link does not automatically make someone a parent. Siblings need not share both parents unless the question says so. These careful conventions prevent hidden assumptions; if a real test explicitly states a different convention, follow that stated convention.
A teacher’s worked example
Question: A is B’s mother. B is C’s father. What is A to C?
- Underline the target: to C. Start at C, not at A.
- Record facts separately: A is female and parent of B; B is male and parent of C.
- Draw A → B → C. The arrows still point from parent to child.
- Trace back from C: father B, then B’s mother A.
- Name the full path: father’s mother = paternal grandmother.
Why not maternal grandmother? That would need C’s mother as the middle person. Here the middle person B is explicitly C’s father.
Complete a partly worked example
A is B’s mother; B is C’s mother. C → mother B → ____ A. Therefore A is C’s ____. Fill both blanks before reading: mother; maternal grandmother.
A simple decision path
Start at the person whose viewpoint is asked → list each stated relation → check the endpoint’s required gender → choose the most specific justified term. If a required link or gender is missing, say exactly what is unknown.
The checks below reduce the support: first choose the arrow, then identify a relation, then spot an unjustified claim.
A is B’s mother. Which arrow records a parent-to-child link?
Show answer
Correct answer: A
A is the parent and B is the child. The arrow is a drawing convention, not the direction in which the sentence is read.
Option A: Correct: A is the parent, so the parent-to-child arrow starts at A.
Option B: This reverses the given fact. B → A would record B as the parent of A.
Option C: The clue states motherhood, not marriage. Do not add a spouse link.
Option D: The word mother explicitly identifies A as a parent.
Hint: Who is the parent?
A is B’s mother. B is C’s father. What is A to C?
Show answer
Correct answer: B
Start from C: father B, then B’s mother A. A is C’s father’s mother.
Option A: This skips B. A is B’s mother, not a stated mother of C.
Option B: Correct: from C, father B → B’s mother A gives paternal grandmother.
Option C: This would require the middle person to be C’s mother. B is explicitly C’s father.
Option D: The two parent links put A two generations above C, not in C’s sibling generation.
Hint: Follow C → B → A, against the parent arrows.
In A (mother) → B (father) → C, which fact remains unknown?
Show answer
Correct answer: C
Mother fixes A’s gender; father fixes B’s. Being someone’s child does not tell us whether C is a son or daughter.
Option A: This is known: mother explicitly identifies A as female.
Option B: This is known: father explicitly identifies B as male.
Option C: Correct. C is a child, but no clue says son or daughter.
Option D: This is known: C’s father B has mother A.
Hint: Whose gender does “father” describe?
Now take the separate practice
Open this lesson’s Practice test: five new checks, about eight minutes, with explanations after answering. This is a low-stakes learning check, not an official SSC paper. Try without the notes, then return to the exact step that caused an error. The optional time estimate is not an exam speed target.
Comparison note: these prototype modules use parallel versions of the same skills. Repeated exposure can improve your score, so this is a format comparison, not a controlled experiment proving which method is best.
Feedback-design reference: Khan Academy’s Perseus exercise editor and renderer. These worked examples and questions are original, using PPDF’s existing quiz components rather than imported code.
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