Question

An article was sold for Rs. 512 after giving two equal successive discounts on the marked price of Rs. 800. The percentage discount offered is:
1. 18%
2. 16%
3. 20%
4. 15%

Answer 1

Correct Answer - Option 3 : 20%

Given:

SP = Rs.512

MP = Rs.800

Calculation:

⇒ 512 = 800 × (100 - ? /100)

⇒ ? = 36%

Single discount = 36%

Let two equal discounts be a%.

⇒ 36 = (a + a - a²/100)

⇒ a² - 200a + 3600 = 0

⇒ a² - 180a - 20a + 3600 = 0

⇒ a(a - 180) - 20(a - 180) = 0

a = 180% or a = 20%

∴ % discount offered is 20%.