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2010 AMC 10B Question 18

AMC10 · 2010 AMC 10B

Question 18

Positive integers $a,$ $b,$ and $c$ are randomly and independently selected with replacement from the set $\{1, 2, 3,\dots, 2010\}.$

What is the probability that $abc + ab + a$ is divisible by $3?$
  1. $\dfrac{1}{3}$
  2. $\dfrac{29}{81}$
  3. $\dfrac{31}{81}$
  4. $\dfrac{11}{27}$
  5. $\dfrac{13}{27}$