3 A bookseller sells a book at a profit of 10%. If he had bought it at 4% less and sold it for Rs. 6 more, he would have gained 184 % The cost price of the book is

Explanation

Let cost price of the book = Rs. 100x Profit % = 10% 10 => Selling price = 100 × 100x = Rs. 110x 4 Now, new cost price = C′ = 100x − ( 100 × 100x) = Rs. 96x Similarly, new selling price = S′ = Rs. (110x + 6) (S′−C′) 3 => Profit % = C′ × 100 = 18 4 (110x+6)−96x 75 => 96x × 100= 4 14x+6 75 1 => 96x = 4 × 100 14x+6 3 => 96x = 16 3 => 14x + 6 = 16 × (96x) => 14x + 6 = 18x => 18x − 14x = 4x = 6 6 => x = 4 = 1.5 ∴ Cost price = 100 × 1.5 = Rs. 150