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Omni-MATH / There are 8 lily pads in a pond numbered 1,2,…,8. A frog starts on lily pad 1. During the i-th second, the frog jumps from lily pad i to i+1, falling into the water with probabilit…

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problem

There are 8 lily pads in a pond numbered 1,2,…,81,2, \ldots, 8. A frog starts on lily pad 1. During the ii-th second, the frog jumps from lily pad ii to i+1i+1, falling into the water with probability 1i+1\frac{1}{i+1}. The probability that the frog lands safely on lily pad 8 without having fallen into the water at any point can be written as mn\frac{m}{n}, where m,nm, n are positive integers and gcd(m,n)=1\operatorname{gcd}(m, n)=1. Find 100m+n100 m+n.
Plain-text mathematical notation (without MathML)
There are 8 lily pads in a pond numbered 1,2,…,8. A frog starts on lily pad 1. During the i-th second, the frog jumps from lily pad i to i+1, falling into the water with probability (1)/(i+1). The probability that the frog lands safely on lily pad 8 without having fallen into the water at any point can be written as (m)/(n), where m,n are positive integers and gcd(m,n)=1. Find 100m+n.
Original LaTeX notation
There are 8 lily pads in a pond numbered $1,2, \ldots, 8$. A frog starts on lily pad 1. During the $i$-th second, the frog jumps from lily pad $i$ to $i+1$, falling into the water with probability $\frac{1}{i+1}$. The probability that the frog lands safely on lily pad 8 without having fallen into the water at any point can be written as $\frac{m}{n}$, where $m, n$ are positive integers and $\operatorname{gcd}(m, n)=1$. Find $100 m+n$.

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