Answer:
$460.
Step-by-step explanation:
[tex]Percentage\ change = (\frac{Original\ Price\ - Discounted\ Price}{Original\ Price})100\\\\15=(\frac{x-391}{x})100\\\\15x=(x-391)100 \\\\15x/100=x-391\\0.15x=x-391\\391=x-0.15x\\391=0.85x\\391/0.85=x\\460=x\\[/tex]
So the price yesterday was $460