If you can say that an application is 90% working, then you can probably divide it into at least two cleanly separated parts: one that works, and one that is erroneous. So, the more correct way to state this would be that x% of your program works. (Unfortunately for you, x may be much lower than 90. Think edge cases.)
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If you can say that an application is 90% working, then you can probably divide it into at least two cleanly separated parts: one that works, and one that is erroneous. So, the more correct way to state this would be that x% of your program works. (Unfortunately for you, x may be much lower than 90. Think edge cases.)