Question
A Shopkeeper gives 5 articles free on the purchase of
every 15 articles. He also allow a discount of 20% to customer and still earn 20% profit. Find the ratio of the cost price to the marked price of the article?Solution
% Discount in getting free items (a) = (free items/ total items) x 100 = [5/(5+15)] x 100 = 25% Next % discount (b) = 20 So net discount(%) = a+b -(ab/100) = 25 + 20 - (25 x 20)/100 = 40% CP MRP (100 - D) (100 + P%) (100 - 40) : (100+20) 6 0 : 120 1 : 2
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