find area under non-standard normal curve (i.e. units not percentages)


I would like some advice on how to calculate the area under a non-standard normal curve, in its own units, not relative to a standard-normal curve. Example distribution characteristics:

Mean :500
Standard Deviation: 100
Point of interest: 550

By finding the relevant Z-score ((550-500)/100), I know that 31% of the area under the curve lies above 550. How do I convert that 31% back into units/terms of the non-standard normal curve?

Through simulation, I believe the answer is roughly 570, but I don’t know truly calculate it.

Thank you.


Ambassador to the humans
You're not really making any sense. If you're asking "which point has 31% of the area above it" then the answer (assuming you did things correctly) should be 550 exactly because of the way you calculated that 31%...