Adjusting profit with a different selling price: A person sells an article for ₹ 3,600 and earns a profit of 20%. Had he sold the article for ₹ 3,150, what profit percentage would he have earned?

Introduction / Context:
Knowing one profit scenario allows computation of CP. Then evaluate the profit percentage at a different selling price based on the same CP.

Given Data / Assumptions:

• SP1 = ₹ 3,600 at 20% profit ⇒ SP1 = 1.20 * CP.
• Alternative SP2 = ₹ 3,150.

Concept / Approach:
CP = SP1 / 1.20. Profit% at SP2 = (SP2 − CP)/CP * 100.

Step-by-Step Solution:
CP = 3,600 / 1.20 = ₹ 3,000Profit at SP2 = 3,150 − 3,000 = ₹ 150Profit% = 150 / 3,000 * 100 = 5%

Verification / Alternative check:
At SP1, the margin is ₹ 600 (20% of 3,000). At SP2 the margin is ₹ 150, which is 5% of 3,000—consistent.

Why Other Options Are Wrong:

• 4% / 6% / 10%: do not equal the computed 150/3,000 * 100.

Common Pitfalls:

• Mistaking the base as SP2 or averaging percentages. Always compute on CP.

Final Answer:
5%