Question 153118
Let w be the wholesale price. Let r be the retail shelf price 
clubPrice = w * 1.08 (8% markup)
storePrice = 0.9 r (10% off, or 90% of the retail shelf price)

Find the r where the club price is equal to the discounted store price
{{{1.08w = 0.9r}}}
{{{1.08w/0.9 = r}}}
{{{1.2w = r}}}
So r is 120% of w. Which means the store markup must be 20% or more for the club price to be a better deal than the discounted store offer.