Selling a coat at Rs 1425 yields a gain that is 6% more than the gain when selling it at Rs 1353. Find the cost price of the coat.

Introduction:
Two selling prices produce gains that differ by 6 percentage points. Express gains relative to the unknown cost price (CP) and equate the difference to 6%.

Given Data / Assumptions:

• SP1 = Rs 1425, SP2 = Rs 1353
• Gain% at SP1 is 6 percentage points more than at SP2

Concept / Approach:
Gain% = (SP − CP)/CP. Difference: [(1425 − CP)/CP] − [(1353 − CP)/CP] = 0.06.

Step-by-Step Solution:
[(1425 − CP) − (1353 − CP)] / CP = 0.06(72) / CP = 0.06 ⇒ CP = 72 / 0.06 = 1200

Verification / Alternative check:
Gain% at 1353: (1353 − 1200)/1200 = 12.75%. At 1425: (1425 − 1200)/1200 = 18.75%. Difference = 6%.

Why Other Options Are Wrong:
1000, 1250, 1500: Do not produce a 6% difference with the given SPs.

Common Pitfalls:
Using 6% of SP instead of 6 percentage points of gain on CP.

Final Answer:
Rs. 1200