A man buys a toy for Rs. 25 and sells it for Rs. 30. His gain percent is = ?

Answer: Option A

According to the question,
Cost price = Rs. 25
Selling price = Rs. 30
Profit = Selling price - Cost price
= 30 - 25
= Rs. 5
$$\begin{array}{rl}& \text{Profit}\%=\frac{5}{25}\times 100\\ & =20\%\end{array}$$