Correct Answer - Option 3 : 80

**Given:**

A shopkeeper marked a price of an article at x% above the cost price and he sold it discount of 0.5x%, then he earns 8% profit.

**Calculation:**

According to the question,

⇒ x – 0.5x – x(0.5x)/100 = 8

⇒ 0.5x – x^{2}/200 = 8

⇒ x^{2} – 100x + 1600 = 0

⇒ x^{2} – 80x – 20x + 1600 = 0

⇒ x(x – 80) – 20(x – 80) = 0

⇒ (x – 80)(x – 30) = 0

⇒ x = 80, 20

According to the condition,

⇒ x = 80

**∴ The value of x is 80.**