Question Detail
Question
In a class of 50 students, 30 speak Hausa, 16 Igbo, 21 Yoruba. If 8 speak Hausa & Igbo, 11 Hausa & Yoruba, 6 Igbo & Yoruba, and all speak at least one language, how many speak all three?
Correct Answer
Option A is the correct answer.
Detailed Explanation
Using inclusion-exclusion: 30+16+21-(8+11+6)+x=50 → 67-25+x=50 → 42+x=50 → x=8.
Hint
Apply n(A∪B∪C)=n(A)+n(B)+n(C)-n(A∩B)-n(B∩C)-n(A∩C)+n(A∩B∩C)