2021 AMC 10B Problems/Problem 4
Contents
Problem
At a math contest, 
students are wearing blue shirts, and another 
students are wearing yellow shirts. The 132 students are assigned into 
pairs. In exactly 
of these pairs, both students are wearing blue shirts. In how many pairs are both students wearing yellow shirts?
Solution
There are 
students paired with a blue partner. The other 
students wearing blue shirts must each be paired with a partner wearing a shirt of the opposite color. There are 
students remaining. Therefore the requested number of pairs is 
~Punxsutawney Phil
Video Solution by OmegaLearn (System of Equations)
~ pi_is_3.14
Video Solution by TheBeautyofMath
https://youtu.be/gLahuINjRzU?t=626
~IceMatrix
| 2021 AMC 10B (Problems • Answer Key • Resources) | ||
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