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2014 AMC 12B Question 22

AMC12 · 2014 AMC 12B

Question 22

In a small pond there are eleven lily pads in a row labeled $0$ through $10.$ A frog is sitting on pad $1.$ When the frog is on pad $N,$ $0 \lt N \lt 10,$ it will jump to pad $N - 1$ with probability $\dfrac{N}{10}$ and to pad $N + 1$ with probability $1 - \dfrac{N}{10}.$ Each jump is independent of the previous jumps. If the frog reaches pad $0$ it will be eaten by a patiently waiting snake. If the frog reaches pad $10$ it will exit the pond, never to return. What is the probability that the frog will escape being eaten by the snake?
  1. $\dfrac{32}{79}$
  2. $\dfrac{161}{384}$
  3. $\dfrac{63}{146}$
  4. $\dfrac{7}{16}$
  5. $\dfrac{1}{2}$