Oranges are bought at 6 for Rs.20 and sold at 4 for Rs.18. Find the gain or loss per cent.


CP of 6 oranges = Rs.20


CP of 1 orange = Rs. 20/6


SP of 4 oranges = Rs.18


SP of 1 orange = Rs. 18/4


Gain = SP –CP





= 35%


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