SSC GD 2023 PYQ — Question 49

SSC GD Constable (English) - 17 Jan 2023 - Shift 2 • Quantitative Aptitude • Q49

A pen costs ₹121.5 and its marked price is ₹150. What should be two equal successive percentage discounts on marked price to have no profit or loss?

Show answer & explanation

Correct answer: D

Explanation

The correct answer is Option 4 i.e. 10%.

Let each successive discount be x%

The cost price (CP) of the pen is ₹121.5

The marked price (MP) of the pen is ₹150

After two successive discounts of x%, the selling price (SP) should be equal to the CP, which means no profit or loss.

Therefore, we can set up two equations:

Selling price after two discounts: SP = MP × (1 - x/100)2

Selling price equals cost price: SP = CP = ₹121.5

Substituting equation 1 into equation 2, we get:

⇒ ₹121.5 = ₹150 × (1 - x/100)2

Simplifying the equation:

⇒ 0.81 = (1 - x/100)2

Taking the square root of both sides:

⇒ 0.9 = 1 - x/100

⇒ x/100 = 0.1

⇒ x = 10%

Therefore, each successive discount should be 10% to achieve no profit or loss