A shopkeeper bought certain number of pens at the rate of 20 Rs60 and the same number at 30 for Rs40. After that he realized that he had bought only 60% of the required number of pens. He bought the rest at 25 for Rs75. He sold the pens at 12 for Rs35. Find his profit/loss %?

Assume he bough 60 pens each for both the Price (60 and 40) Then you'll have 120 pends with C.P as 240 But 120 pens are just 60% of actually required -> You require 200 pens so you buy 80 pens (25 for Rs75 i.e. Rs3/each) So total pens 200 with C.P = 500 C.P per pen = 2.5 S.P is 35/12 Calculate profit. Approximately I can tell it will be less than 20%