Also, duplicate.

Addition has been done; changing a boolean to a string has been done. Combining them does not make a novel kata.

Also, no random tests.

Test coverage is glaringly incomplete. "Try again" is never even checked.

There is an incorrect JS language version ( with some Python code ).

1. In the beginning of description:

   Given a string, replace all vowels (a, e, i, o, u) with 0...

   But then at the last paragraph:

   Vowels (a, e, i, o, u, A, E, I, O, U) should be replaced by 0...

   So, which is the correct lists of vowels?

2. No sample tests

3. No random tests

1. No sample tests
2. No random tests
3. You shouldn't use rounding to work around float inaccuracy, use approximate equality instead