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2007 AMC 10A Question 25

AMC10 · 2007 AMC 10A

Question 25

For each positive integer $n,$ let $S(n)$ denote the sum of the digits of $n.$ For how many values of $n$ is $n + S(n) + S(S(n)) = 2007?$
  1. $1$
  2. $2$
  3. $3$
  4. $4$
  5. $5$