Question 981184
Let p be the original price.


Mark-up 20%.
{{{p*(1.20)}}}


Discount 20%.
This is 80% of the marked-up price.
{{{p(1.20)(0.80)}}}


"In the end,  $300 less than p".
(?)
Only sensible understanding is "in the end" means the result of the described 20% discount.
{{{(0.8)(1.2)p=p-300}}}
-
{{{(0.8)(1.2)p-p=-300}}}
{{{p-0.8*1.2p=300}}}
{{{highlight(p=7500)}}}



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You had a correct equation.  All the analysis and then you did not just do the simple arithmetic to finish?