By selling 36 oranges for ₹24 a man losses 20%. How many should he sell for ₹18 to earn 20%.

18

Loss 20% = \(\frac{4}{5}\) , Gain 20% = \(\frac{6}{5}\)

⇒ In rs.24, no. of oranges to be sell to cover 20% loss = 36 × \(\frac{4}{5}\)

⇒ In rs.24, no. of oranges to be sell to gain 20% profit = 36 × \(\frac{4}{5}\) × \(\frac{5}{6}\)

⇒ In rs.01, no. of oranges to be sell to gain 20% profit = 36 × \(\frac{4}{5}\) × \(\frac{5}{6}\) × \(\frac{1}{24}\)

⇒ In rs.18, no. of oranges to be sell to gain 20% profit = 36 × \(\frac{4}{5}\) × \(\frac{5}{6}\) × \(\frac{18}{24}\) = 18