OP solved it, closing

It expects string I believe.

Ok. So, I did some research. It seems draft is the distance of the water line to the bottom of the ship. With crew on board, the draft is going to increase. What you want is that the draft due to the gold (only) to be 20. So the draft passed in the test is the measured draft. You need to calculate and see if this value minus the draft contributed by the crew is more than 20 (Since you want the draft contributed by the goods to be more than 20).

Note that the length of the input argument num is between 0 and 6. It has, may be, 2 digits.

Try to rearrange your code to universal one for all cases.

Hmm, that's a shame. The error message should point out that the exercise requires a function which takes two strings and returns another string, not a number.

it was static instead of class before

I can't see your solution. Please, copy it to comments with mark "Mark as having spoiler content".

Trying to solve this kata with Javascript. I've stucked on Incorrect hex-string length. What kind of output should i do to pass this test? Thanks. P.S. I've tried return false and return 'Incorrect hex-string length', both are wrong.