Question

a vendor bought 100 oranges for Rs 200 he sold 20 of them at a gain of 5%. At what gain percent must he sell the remainder so as to gain 30% on the whole

Answer 1

Answer:

Cp of oranges = 200  profit on it, 30% of ₹200 = 30/100 × 200=60 Total selling price = 200 + 60 = 260 Cp of 100 oranges = ₹200 Cp of 1 orange = ₹200÷100 = 2 Cp of 20 oranges = 2 × 20 = ₹40 Gain on 20 oranges = 5 % of 40 Gain = 40 × 5/100 = ₹2 Total SP of 20 oranges = ₹40 + ₹2 = ₹42 SP of all the oranges with profit of 30% -  SP of 20 oranges = SP of remaining oranges with profit I.e  ₹260 - ₹42 = ₹218  So he should sell it for ₹218 to get overall gain of 30%    

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