In a group, 40 people like tea, 32 like coffee, and 18 like both. How many like at least one drink?
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Answer and explanation
Correct answer: 54
“At least one drink” means the union of the tea and coffee groups. People who like both drinks are included in both totals, so they have been counted twice. Subtract the overlap once: n(Tea ∪ Coffee) = 40 + 32 − 18 = 54. Thus, 54 people like tea, coffee, or both. The word “at least” includes those who like both.
Frequently asked questions
What is the correct answer to this question?
54
Why is this the correct answer?
“At least one drink” means the union of the tea and coffee groups. People who like both drinks are included in both totals, so they have been counted twice. Subtract the overlap once: n(Tea ∪ Coffee) = 40 + 32 − 18 = 54. Thus, 54 people like tea, coffee, or both. The word “at least” includes those who like both.
Which subject and chapter does this question cover?
This is a Class 10 Mathematics question. Chapter: Sets. Topic: Venn Diagrams.
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