2024 · Q34
In a class containing 200 students, n students prefer both tea and coffee; 2n students prefer coffee, 3n students prefer tea; 4n students prefer neither tea nor coffee. What is the value of n?
Elementary MathematicsSet Theory
- A20
- B25
- C30
- D35
Explanation
Let T = tea, C = coffee. |T ∪ C| = 200 − 4n and also = 3n + 2n − n = 4n. So 4n = 200 − 4n, giving 8n = 200 and n = 25 — option B.