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2003 AMC 12B Question 19

AMC12 · 2003 AMC 12B

Question 19

Let $S$ be the set of permutations of the sequence $1,$ $2,$ $3,$ $4,$ $5$ for which the first term is not $1.$ A permutation is chosen randomly from $S.$ The probability that the second term is $2,$ in lowest terms, is $\frac{a}{b}.$ What is $a + b?$
  1. $5$
  2. $6$
  3. $11$
  4. $16$
  5. $19$