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Critical Thinking Medium 2 min

A survey of 100 people finds that 80 like tea and 70 like coffee. Can you conclude that exactly 50 people like both?

Hint
Use the inclusion-exclusion principle.

Answer

No. At least 50 like both, but the exact number is not determined.

Explanation

The minimum overlap is 80 + 70 - 100 = 50. The actual overlap could be greater.

Step-by-Step Solution

Minimum overlap = 80 + 70 - 100 = 50.
Therefore at least 50 people like both, but the exact overlap is unknown.
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