2020 AIME I Problems/Problem 7: Difference between revisions
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== Solution == | == Solution == | ||
We will be selecting girls, but <i>not</i> selecting boys. We claim that the amount of girls selected and the amount of guys not selected adds to <math>12</math>. This is easy to see: if <math>k</math> women were chosen, then <math>k + (11 - k + 1) = 12</math>. Therefore, we simply take <math>\binom{23}{12} \implies \boxed{081}</math>. ~awang11's sol | |||
==See Also== | ==See Also== | ||
Revision as of 16:15, 12 March 2020
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Problem
Solution
We will be selecting girls, but not selecting boys. We claim that the amount of girls selected and the amount of guys not selected adds to 
. This is easy to see: if 
women were chosen, then 
. Therefore, we simply take 
. ~awang11's sol
See Also
| 2020 AIME I (Problems • Answer Key • Resources) | ||
| Preceded by Problem 6 |
Followed by Problem 8 | |
| 1 • 2 • 3 • 4 • 5 • 6 • 7 • 8 • 9 • 10 • 11 • 12 • 13 • 14 • 15 | ||
| All AIME Problems and Solutions | ||
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