MathDB
2018 Theme #8

Source:

November 13, 2018
probability

Problem Statement

Crisp All, a basketball player, is dropping dimes and nickels on a number line. Crisp drops a dime on every positive multiple of 1010, and a nickel on every multiple of 55 that is not a multiple of 1010. Crisp then starts at 00. Every second, he has a 23\frac{2}{3} chance of jumping from his current location xx to x+3x+3, and a 13\frac{1}{3} chance of jumping from his current location xx to x+7x+7. When Crisp jumps on either a dime or a nickel, he stops jumping. What is the probability that Crisp stops on a dime?