A shopkeeper bought toffees at the rate of 6 for ₹4 and sold them at the rate of 4 for ₹6. His gain percentage is

125%

CP of toffees at the rate of 6 = ₹4

CP of toffees at the rate of 6 × 4 = 4 × 4 = 16

SP of toffees at the rate of 4 = ₹6

SP of toffees at the rate of 4 × 6 = 6 × 6 = 36

Gain percentage = \(\frac{36 - 16}{ 16 }\) × 100%

= \(\frac{20}{ 16 }\) × 100%

= 125%

The correct answer is Option (2) → 125%