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2003 AMC 10B Question 13

AMC10 · 2003 AMC 10B

Question 13

Let $\clubsuit(x)$ denote the sum of the digits of the positive integer $x.$ For example, $\clubsuit(8)=8$ and $\clubsuit(123)=1+2+3=6.$ For how many two-digit values of $x$ is $\clubsuit(\clubsuit(x))=3?$
  1. $3$
  2. $4$
  3. $6$
  4. $9$
  5. $10$