AMC / AIME · Pigeonhole Principle · Easy
Pigeonhole Principle: What is the minimum number of people needed to guarantee that two were born on the same day of the week?
Forced collisions.
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What is the minimum number of people needed to **guarantee** that two were born on the same day of the week?
Hint and answer
Concept to use
Basic form.
Hint
Seven weekdays → .
Answer
8
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