Difference between revisions of "2020 AIME I Problems/Problem 7"
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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
Note: Please do not post problems here until after the AIME.
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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