The correct identification of Hans's error is:
He did not finish the problem. He should have divided 1618 by 2 to find the square root.
This response accurately points out that Hans didn't proceed to calculate the hypotenuse correctly after squaring the legs and summing them up. The correct approach is to take the square root of \(c^2\), rather than dividing \(1618\) by \(2\). However, it's important to clarify that he wouldn't actually divide by \(2\) at any point; he should take the square root of \(1618\) directly. So while this response indicates that he didn't complete the problem, it is misleading in the approach to finding the square root.
The accurate root should be calculated as \(c = \sqrt{1618}\) and should not involve dividing by \(2\).