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| − | ==Problem==
| + | #redirect [[2022 AMC 12A Problems/Problem 24]] |
| − | How many strings of length <math>5</math> formed from the digits <math>0</math>,<math>1</math>,<math>2</math>,<math>3</math>,<math>4</math> are there such that for each <math>j\in\{1,2,3,4\}</math>, at least <math>j</math> of the digits are less than <math>j</math>? (For example, <math>02214</math> satisfies the condition because it contains at least <math>1</math> digit less than <math>1</math>, at least <math>2</math> digits less than <math>2</math>, at least <math>3</math> digits less than <math>3</math>, and at least <math>4</math> digits less than <math>4</math>. The string <math>23404</math> does not satisfy the condition because it does not contain at least <math>2</math> digits less than <math>2</math>.)
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| − | <math>\textbf{(A) }500\qquad\textbf{(B) }625\qquad\textbf{(C) }1089\qquad\textbf{(D) }1199\qquad\textbf{(E) }1296</math>
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| − | == Solution 1 By OmegaLearn using Complementary Counting ==
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| − | https://youtu.be/jWoxFT8hRn8
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| − | ~ pi_is_3.14
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| − | == See Also ==
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| − | {{AMC10 box|year=2022|ab=A|num-b=23|num-a=25}}
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| − | {{MAA Notice}}
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| − | == See Also ==
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| − | {{AMC10 box|year=2022|ab=A|num-b=23|num-a=25}}
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| − | {{MAA Notice}}
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