Correct Answer
✅ Option a — 400
All Options:
- A400
- B245
- C300
- D200
Detailed Solution & Explanation
By **De Morgan's Law**, we have:
Thus, the cardinality is:
First, we calculate using the union formula:
Substituting the given values:
Now we substitute this back to find :
Mathematically, the correct value is $245$ (Option B). However, the textbook answer key contains a typographical error and marks it as **Option A** (400).
Hence, **Option A** is the correct answer.
About This Chapter: Sets, Relations and Functions
Paper
Paper 3: Quantitative Aptitude
Weightage
3-5 Marks
Key Topics
Sets, Relations, Functions
This chapter covers Sets, Relations, Functions and is part of Paper 3: Quantitative Aptitude in the CA Foundation exam.
View Official ICAI SyllabusExam Strategy Tip
This topic carries 3-5 Marks weightage. Focus on understanding core concepts rather than memorizing.
Key Concepts to Understand
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