A shopkeeper allows 4% discount and gives 1 article free on purchase of 15 articles. He earns 35% profit during the transaction. By what percent above the cost price he marked goods?

50%

Let marked price = 100

Price after discount of 4% = 100 - 4 = 96

Again, he gives 1 article on purchase of 15 article

discount of 1 on every set of 16

Discount on 96 = \(\frac{96}{16}\) = 6

Total discount = 4 + 6 = 10%

SP after discount = 100 × 90% = 90

Cost price after 35% profit = 90 x\(\frac{100}{135}\) = \(\frac{200}{3}\)

% of marked price = \(\frac{(100 - \frac{200}{3})}{\frac{200}{3}}\) x 100 = 50%