The marked price of the a watch is Rs. 1600. The shopkeeper gives successive discount of 10% and x% to the customer. It the customer pays Rs. 1224 for the watch, the value of x is = ?

A. 5%

B. 10%

C. 15%

D. 20%

Answer: Option C

Solution(By Examveda Team)

Marked price of watch = Rs. 1600
After 1st discount of 10%
$$\eqalign{ & {\text{ = 1600}} \times \frac{{90}}{{100}} \cr & {\text{ = Rs}}{\text{. 1440}} \cr} $$
Customer pays (final selling price) = Rs. 1224
$$\eqalign{ & \frac{x}{{100}} \times 1440 = \left( {1440 - 1224} \right) \cr & \frac{x}{{100}} \times 1440 = 216 \cr & x = \frac{{216 \times 100}}{{1440}} \cr & x = 15\% \cr} $$