A shopkeeper gives two successive discounts on an article marked Rs. 450. The first discount given is 10%. If the customer pays Rs. 344.25 for the article, the second discount given is -

Answer: Option D

Let the second discount rate be x%
Then,
= (100 - x)% of 90% of 450 = 344.25
$$\begin{array}{rl}& \Rightarrow \frac{100-x}{100}\times \frac{90}{100}\times 450=344.25\\ & \Rightarrow \left(100-x\right)=\left(\frac{34425}{9\times 45}\right)=85\\ & \Rightarrow x=15\end{array}$$
∴ Second discount rate = 15%