Question
Profit on selling 40 pens equals selling price of 12
books while loss on selling 40 books equals selling price of 16 pens. Also profit percentage equals to the loss percentage and cost of a pen is half of the cost of a book. What is the ratio of selling price of pen to the selling price of a book?Solution
c=2a Profit = 40(b-a) = 12d Loss = 40(c-d) = 16d Profit% = 12d/40a × 100 Loss% = 16b/40c × 100 Since, the percentage values are equal Therefore, 12d/40a ×100 = 16b/40c ×100 3d/10a= 4b/10c 3d/a = 4b/2a b/d = 3/2
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