In a group of students, study Sinhala, study Tamil and study both. How many study at least one of the two languages?
Answer and explanation
Correct answer: A.
- Step 1: Use .
- Step 2: .
Answer
.
Why not the others: is what you get if you add without removing those counted twice. is what you get if you subtract the overlap twice. is what you get if you add the overlap.
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