Cannot Be Determined
Cannot Be Determined problems present blood relation scenarios where the given information is insufficient to establish a unique relationship between two persons. These problems test your ability to recognize when data is incomplete or leads to multiple possible interpretations.
What You'll Learn
Introduction to Cannot Be Determined
Cannot Be Determined problems present blood relation scenarios where the given information is insufficient to establish a unique relationship between two persons. These problems test your ability to recognize when data is incomplete or leads to multiple possible interpretations.
Prerequisites
How to Solve Cannot Be Determined Problems
Step 1: Read all statements and identify all persons mentioned
Step 2: Build the family tree using all given information
Step 3: If any person's gender is unknown, check if it affects the relationship in question
Step 4: If any generational link is missing, check if alternative placements are possible
Step 5: List all possible relationships that satisfy all given statements
Step 6: If more than one distinct relationship is possible, answer is 'Cannot Be Determined'
Step 7: If all possibilities yield the same relationship, then it is determined
Example Problem
Example: 'A is the brother of B. C is the sibling of A.' How is C related to B? Solution: Step 1: A is brother of B → A is male, B could be male or female Step 2: C is sibling of A → C shares parents with A Step 3: C could be brother or sister of A Step 4: C could be brother/sister of B (since same parents) Step 5: Without knowing C's gender or B's gender, C could be brother, sister, or sibling of B Step 6: Multiple possibilities exist Answer: Cannot Be Determined (C could be brother or sister of B)
Pro Tips & Tricks
- Missing gender information often leads to 'cannot be determined'
- Missing generational links (e.g., no parent-child connection) often leads to ambiguity
- If a person is referred to only by a pronoun (he/she) but the antecedent is unclear, data is insufficient
- If multiple family tree configurations satisfy all statements, answer is ambiguous
- 'Cannot be determined' is different from 'no relation'—there is a relation, but it's not uniquely identifiable
- Watch for statements that seem to give information but actually don't (e.g., 'A is a person')
Shortcut Methods to Solve Faster
Common Mistakes to Avoid
Practice Worksheets
Practice makes perfect! Work through these worksheets to master Cannot Be Determined. Each worksheet contains 20 questions with detailed explanations. Start from Worksheet 1 and progress through increasing difficulty levels.
Exam Importance
Cannot Be Determined is an important topic for various competitive exams. Here's how frequently it appears:
Ready to Master Cannot Be Determined?
Start with Worksheet 1 and work your way up to expert level! Each worksheet includes: