MathDB
Birthdays falling in the same month

Source: AMC 10 2011 b Problem 11

February 24, 2011
pigeonhole principleAMC

Problem Statement

There are 5252 people in a room. What is the largest value of nn such that the statement "At least nn people in this room have birthdays falling in the same month" is always true?
<spanclass=latexbold>(A)</span> 2<spanclass=latexbold>(B)</span> 3<spanclass=latexbold>(C)</span> 4<spanclass=latexbold>(D)</span> 5<spanclass=latexbold>(E)</span> 12 <span class='latex-bold'>(A)</span>\ 2 \qquad <span class='latex-bold'>(B)</span>\ 3 \qquad <span class='latex-bold'>(C)</span>\ 4 \qquad <span class='latex-bold'>(D)</span>\ 5 \qquad <span class='latex-bold'>(E)</span>\ 12