A man bought two bicycles for ₹3,000 each. If he sells one bicycle at a profit of 10%, then for how much percentage profit should he sell the other bicycle so that he makes a profit of 20% on the whole?

30 Percent

                                         CP                    SP

Profit of 10% on first    =    10                     11

Profit of x on second    =     10                     _   (CP is same)

                                    ———————————— 

Overall profit 20%      =     20                      24

So, SP of second = 24 - 11 = 13

Profit = 13 - 10 = 3

So, \(\frac{3 × 100}{10}\) = 30%