A vendor buys oranges at Rs 26 per dozen and sells them at 5 for Rs 13. Find his gain percent.

Explanation

To solve the problem step by step, we will calculate the cost price, selling price, gain, and gain percent of the oranges.

### Step 1: Calculate the Cost Price of One Orange
The vendor buys oranges at Rs 26 per dozen. Since one dozen contains 12 oranges, we can find the cost price of one orange.

\[ \text{Cost Price (CP) of 1 orange} = \frac{\text{Cost Price of 12 oranges}}{12} = \frac{26}{12} = \frac{13}{6} \text{ Rs} \]
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