% Asked Hint
Should be below 20%
Above 35% indicates a serious problem with the exercise that needs to be addressed
% Asked Solution
Ideally should be below 20%
To judge the power of the hint, it's also worth looking at the difference between these metrics.
Ideally a hint should get the learner halfway to the solution, so the %asked solution should be about half %asked hint. If they are approximately equal, the hint wasn’t very helpful, and should be rewritten.
For additional help on exercises, see these articles