The most important thing to note about DRY is that it's not about code -- it's about knowledge. You should not repeat knowledge -> logic, constants, etc. If the temperature is 87 and the price of the widget is 87 that is coincidence and not repetition.
There should just be one source of truth for any logic or process. If you duplicate that then bad things will eventually happen.
There should just be one source of truth for any logic or process. If you duplicate that then bad things will eventually happen.