We can factor 120 as 4 × 30. This is nice because 4 is a perfect square and the only one hiding inside our radicand. It wasn't doing a very good job, obviously, since we found it right away. Given this, 
We can't simplify any more. 30 factors completely as 2 × 3 × 5 and no factor of 30 is a perfect square, so we're done. The nicest it ever looks is  .
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