Skip to content / Đến nội dung
ThichHocToan.com

2010 AMC 12B Question 16

AMC12 · 2010 AMC 12B

Question 16

Positive integers $a,$ $b,$ and $c$ are randomly and independently selected with replacement from the set $\{1, 2, 3, \ldots, 2010\}.$ 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. $\dfrac{13}{27}$