A housewife saved Rs. 2.50 in buying a dress on sale. If she spent Rs. 25 for the dress, approximately how much percent she saved in the transaction ?

Answer: Option B

House wife spends Rs. 25 on dress and saved Rs. 2.50
Total transaction = 25 + 2.50 = Rs. 27.50
$$\begin{array}{rl}& \text{Save }\%=\frac{2.50}{27.50}\times 100\\ & =\frac{100}{11}\%\\ & =9\%\text{ ( approx)}\end{array}$$