I can't really give you any specific formulas, but I can show you the mechanics of setting this up:
Assume cell A1 is where the 3 digit number is entered. In cell D4 you could put the formula
=(A1*3); in cell E7 you could put the formula
=(A1^2); repeat, using other formulas in any other 3 cells.
As soon as the 3 digit number is entered in A1, the other cells will recalculate based on the A1 value. Of course it will be your job to come up with formulas that guarantee
all the results will be 3 digit numbers.
Good luck.
Just curious, but why no macros?