Question 752253
{{{x}}}= marked "original" price (in $)
discounted price = {{{x-0.15x=0.85x}}}
The profit would be the discounted price minus the cost,
profit ={{{0.85x-85}}}
As a percentage of the $85 cost, the profit would be
{{{(0.85x-85)/85}}}x100%=20% or
{{{(0.85x-85)/85=0.20}}} --> {{{0.85x-85=0.20*85}}} --> {{{0.85x-85=17}}} --> {{{0.85x=85+17}}} --> {{{0.85x=102}}} --> {{{x=102/0.85}}} --> {{{highlight(x=120)}}}
The retailer should mark the original price as $120.
The customer would get a 15% discount, which would reduce the price by $18, to $102.
Selling the shoes at $102, the retailer would have a profit of
$102 - $85 = $17, and that $17 is 20% of the $85 cost.