A man sold an article for ₹687 by first giving a d% discount on its marked price, and then another discount having the same nominal value (in ₹). If the marked price of the article is ₹1145, then what is the value of d?

Correct option is C

Given:

Marked Price (MP) = ₹1145

Selling Price (SP) = ₹687

Concept Used:

First Discount = $$\frac{d}{100} \times$$​ 1145

Solution:

Price after first discount:

New Price = 1145 $$- \frac{d}{100} \times$$​ 1145

Price after second discount:

Final Selling Price = $$\left(1145 - \frac{d}{100} \times 1145\right) - \frac{d}{100} \times 1145$$​

Given that the final selling price is ₹687

687 = 1145 $$- 2 \times \frac{d}{100} \times$$​ 1145

687 = 1145 - $$\frac{2d}{100} \times$$​ 1145

​$$\frac{2d}{100} \times$$​ 1145 = 1145 - 687

​$$\frac{2d}{100} \times$$​ 1145 = 458

2d $$\times$$​ 11.45 = 458

2d = $$\frac{458}{11.45}$$​

2d = 40

d = 20

d = 20%