A shopkeeper gives 20% commission on the retail price of one article and earns 5% profit. If his commission is reduced by 10%, then what is his approximate profit percentage? (Nearest integral value)

18%

Shopkeeper gives 20% commission on the retail price of one article and earns 5% profit means,

80% of MP = 105% of CP

\(\frac{MP}{CP}\) = \(\frac{21}{16}\)

If the commission reduced to 10% means,

90% of MP = x% of CP

\(\frac{MP}{CP}\) = \(\frac{18.9}{16}\) 

Profit = 18.9 - 16 = 2.9

Profit % = \(\frac{1.9 × 100}{16}\) = 18%