A vendor purchased bananas at Rs.40 per dozen and sold them at 10 for Rs. 36. Find his gain or loss per cent.

SP of 1 Banana = 36/10


= Rs.3.6


SP of 1 Dozen Banana = 3.6 × 12


= Rs.43.20


CP of 1 Dozen Banana = Rs.40


Gain = SP – CP


= 43.20 – 40


=3.2



=


= 8%


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