Question Detail
Question
In a class of 40 students, 32 are good in mathematics, 24 in physics, 4 do not take any, how many are good in both mathematics and physics?
Correct Answer
Option C is the correct answer.
Detailed Explanation
Total students = 40, 4 take none, so at least one subject = 36. Using inclusion-exclusion: |M ∪ P| = |M| + |P| - |M ∩ P|. 36 = 32 + 24 - x → 36 = 56 - x → x = 56 - 36 = 20.
Hint
Use the principle of inclusion-exclusion.