Step 1: Find face value of stock purchased.
Market price = 136, face value = ₹100.
Amount invested = ₹6800
Face value of stock bought:
\[
= \frac{6800}{136} \cdot 100 = 50 \cdot 100 = ₹5000
\]
Step 2: Income from 10\% stock on ₹5000:
\[
\text{Income} = \frac{10}{100} \cdot 5000 = ₹500
\]