Question

How many children does ‘X’ have?
I) ‘Y’ is the only son of ‘Z’ who is wife of ‘X’.
II) ‘W’ is a son of ‘Y’.

• A. Statement I alone is sufficient to answer the question
• B. Statement II alone is sufficient to answer the question.
• C. Statement I and II together are sufficient to answer the question but neither statement alone is sufficient.
• D. Statement I and II together are not sufficient to answer the question and additional data is required.

Hint:

In family problems, “only son” does not mean “only child.” Always check for possibility of daughters or additional members.

Answer 1

The Correct Option is D

Concept: In family relation problems, we must identify relationships clearly and check whether the number of children can be uniquely determined.
Step 1: Analyze Statement I alone.
‘Z’ is the wife of ‘X’.
‘Y’ is the only son of ‘Z’, hence also a child of ‘X’.
However, it does not tell whether ‘X’ has daughters or more children.
Statement I alone is NOT sufficient.
Step 2: Analyze Statement II alone.
‘W’ is a son of ‘Y’.
This gives information about the next generation, not about children of ‘X’.
Statement II alone is NOT sufficient.
Step 3: Combine both statements.
From I: X has at least one child (Y).
From II: W is child of Y (grandchild of X).
Still, total number of children of X cannot be determined.

Hence, even both statements together are NOT sufficient.