Yes, 1.0 and 1.00 are the same value, however, the description states:

You need to round the answer to 2 decimal places and return it as String.

Since you are returning the value as a string, it is possible to format a number like 1 or 1.0 into "1.00". (Italics are hints).

You need to round the answer to 2 decimal places and return it as String.

As strings they're different.