Subtract range from X

[books4cars]

I have a range of cells with numbers which I want to subtract from one number. When I put in =500-X34:X57 I get the #Value error. Some of these cells have a value and some do not.
Please advise.
Thanks

 

[Airfix9]

Do you want to subtract the total of the range from 500 or create a new range of numbers which are the original number subtracted from 500?

If the former: =500-SUM(X34:X57)

If the latter: =500-X34 then copy and paste down the formula to the same size as the range.

If neither, can you please elucidate?

 

[books4cars]

It was the first one. Thanks