Best Answer: You need to work out the original price of the car if the mark-up was exactly 30%.
Whatever the original price was, the salesman would multiply this by 1.30 (same as 130%) to get the final price. So to work backwards, you take the final price ($7800) and DIVIDE by 1.30
On a calculator, 7800 / 1.3 = 6000
So the answer is $6,000