original price = discounted price/ discount rate

in the case cited by you original price would be 24.23/0.51 which is 47.51.
You will have to take care of rounding errors.
"SRedford" wrote:

If I have the discounted price and the discount percentage that that price
represents, what formula do I use to find out what the original price is?

For example:

The discounted price is $24.23
The discount percentage-from-list that $24.23 represents is 51%
What is the list price?

Thanks!