Question 1 · Quantitative Aptitude and Data Interpretation (QA & DI)
MCQ
What is the fundamental test to decide whether a counting problem requires permutations or combinations?
Correct Answer:
B
Step-by-Step Solution
Key idea: This is a definition question testing the core distinction between permutations and combinations.
Step 1: Permutations deal with arrangements where the sequence or position of items is important.
Step 2: Combinations deal with selections where only the identity of the chosen items matters, not their sequence.
Step 3: Therefore, the fundamental "order test" asks: "Does the order matter?" If yes, use permutations; if no, use combinations.
Answer: "Whether the order of the selected items matters." (option B).