By selling 3 dozen ball pens, a shopkeeper earned a profit equal to the selling price of 10 ball pens. Find his profit percentage.
Answer & explanation
Correct answer: option 2
The correct answer is Option (2) → \(38\frac{6}{13}\)%
Selling price \(=\) cost price \(+\) profit. If the profit on 36 pens is the selling price of 10 pens, then the cost of the 36 pens is the selling price of the other 26 pens.
3 dozen \(=36\) pens; take the selling price of one pen as Rs 1
Selling price of 36 pens \(=\) Rs 36
Profit \(=\) selling price of 10 pens \(=\) Rs 10
Cost price of 36 pens \(=36-10=\) Rs 26
Profit per cent \(\displaystyle =\frac{10}{26}\times100=\frac{500}{13}=38\frac{6}{13}\)%
His profit is \(38\frac{6}{13}\)%.