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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.