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2019 AMC 12B Question 4

AMC12 · 2019 AMC 12B

Question 4

A positive integer $n$ satisfies the equation $(n+1)!+(n+2)!=440\cdot n!.$ What is the sum of the digits of $n?$
  1. $2$
  2. $5$
  3. $10$
  4. $12$
  5. $15$