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You could use recursion, let $a_n$ be the number of ways for $n$ steps. Then Leo can hop $1$ step or $2$ steps on the first hop, so $a_n=a_{n-1} + a_{n-2}$. You can calculate $a_1=1$ and $a_2=2$ and use them to find $a_{10}$. This is basically the Fibonacci sequence.