no this is appropriately rated. not everybody recognizes a math problem when they seen one. if you try to implement this 'mechanically' instead of math you fail

edit: after solving, iterative solutions work too, i had an infinite loop. but i ended up implementing the correct math formula which will always work. iterative accumulator based solutions timeout for very large inputs (ex: bouncing_ball(300000000000000, 0.9999999, 1.5)). some 7 kyu kata actually have stress tests with extremely large numbers, so i was wary of this kata.

I do also believe that this is too easy for a 6 kyu, being more like a 7 kyu.

hi, you're going to solve a problem it doesn't matter what you've faced in the description as long as the problem is clear and solvable, just you should put it into your mind and throw it to compiler as a formula.