Answer: 5% profit / 5% लाभ
Explanation: The standard mathematical logic for such a problem dictates that the faulty balance “indicates 1250 gm for a true 1000 gm” (meaning when he claims to sell 1250g, he actually only gives out 1000g).
Let the cost price of 1000g be Rs 1000. While buying, he takes 20% more weight, getting 1200g for Rs 1000.
This makes his actual Cost Price (CP) of 1000 gm = 1000 × (1000/1200) = Rs. 2500/3.
While selling, he sells at 30% below the cost price of the indicated weight (1000g).
So, Selling Price (SP) of 1000gm = 70% of Rs 1000 = Rs 700.
But his balance shows 1250 gm for actual weight of 1000gm. So he actually charges for 1250 gm at the discounted price per gram.
⇒ SP of 1000 gm = Rs. 1250 × (700/1000) = Rs. 875
⇒ Profit = 875 – 2500/3 = 125/3
⇒ % of Profit = (125/3 × 100)/(2500/3) = 5%
व्याख्या:
