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## '1 Step 2 Step' printed from http://nrich.maths.org/

Liam's house has a staircase with $12$ steps. He can go down the steps one at a time or two at a time.

For example, he could go down $1$ step, then $1$ step, then $2$ steps, then $2$, $2$, $1$, $1$, $1$, $1$.

In how many different ways can Liam go down the $12$ steps, taking one or two steps at a time?

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