if understand your questions:

highlight cells-- go to format--selelct cell--number--percentage--ok

now when you type 20 you will get 20%

"ChrisR" wrote:

I was wondering if it is possible to enter a value in a cell and return a
percentage from this value in the same cell.

Example (using n=100)

20 (20.00%)
40 (40.00%)

Here, 20 and 40 are entered values while the complimenting percentages are
calculated and displayed in the same cell. The cells will need to display
both the entered values and calculated percentages.

Thanks in advance,
Chris